Дисертації з теми "Growth increments"

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1

Zhang, Ziyang. "Studies on otolith growth increments in Tilapia species." Thesis, Bangor University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291686.

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2

Gonçalves, Renata Isabel de Sousa. "Growth variability of Greenlandic cod (Gadus morhua L.) estimated by means of otolith annual increments." Master's thesis, Instituto de Ciências Biomédicas Abel Salazar, 2008. http://hdl.handle.net/10216/9326.

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3

Gonçalves, Renata Isabel de Sousa. "Growth variability of Greenlandic cod (Gadus morhua L.) estimated by means of otolith annual increments." Dissertação, Instituto de Ciências Biomédicas Abel Salazar, 2008. http://hdl.handle.net/10216/9326.

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4

COSTA, Denise Fabiana de Moraes. "Aspectos de crescimento e mortalidade do guanhumi (CARDISOMA GUANHUMI) em um manguezal de acesso restrito na Ilha de Itamaracá – PE." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18350.

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FACEPE
O conhecimento dos parâmetros de crescimento e mortalidade em braquiúros é fundamental para a compreensão da sua dinâmica e para o manejo de suas populações. Neste sentido, foram estimados os parâmetros de crescimento e mortalidade para Cardisoma guanhumi Latreille, 1825 (guaiamum), uma espécie com elevada importância socioeconômica no nordeste brasileiro e atualmente considerada pelo Ministério do Meio Ambiente como Criticamente em Perigo de extinção. As amostragens foram efetuadas durante um ano, entre abril de 2015 a março de 2016, na margem superior do mangue do CMA/ICMBio/CEPENE na ilha de Itamaracá, Pernambuco, Brasil. Foram capturados, medidos e pesados 1078 indivíduos (572 machos e 506 fêmeas). Destes, 291 indivíduos foram marcados com microchips PIT ("Passive Integrated Transponder"), para determinação dos parâmetros de crescimento através dos incrementos de peso e tamanho e do crescimento individual. Para a análise dos dados, foram utilizados o método ELEFAN I (baseado na distribuição de frequência de largura de carapaça de 1078 indivíduos), inserido no pacote computacional Fisat II e através da função GrowthTraject (baseada em incrementos individuais de 291 indivíduos marcados com PITs, utilizando o pacote fishmethods (Ambiente de programação “R”). Os indivíduos de C.guanhumi apresentaram largura da carapaça entre 20,9 e 70,0 mm (média: 43,45 mm, desvio padrão: 8,53 mm, mediana: 44,05 mm) o peso total entre 4 e 162 g (média: 45,85 g, desvio padrão: 25,34 g, mediana: 44,0 g). Não houve diferenças significativas, em tamanho médio e peso médio, entre machos e fêmeas. Os parâmetros de crescimento estimados com a função GrowthTraject para 130 incrementos (machos e fêmeas) foram: Linf (tamanho assintótico) = 108,03 mm (largura da carapaça); K (coeficiente de crescimento) = 0,145 ano-1. A Mortalidade total (Z) da população, estimada pelo método Length – converted Catch Curve (pacote FISAT II) usando os parâmetros de crescimento do GrowthTraject foi de = 2,39 ano-1. Não ocorrem capturas comerciais nesta área fechada, portanto, este valor equivale à mortalidade total e natural (Z=M). A idade dos indivíduos capturados variou de 1,49 anos (20,9mm) a 7,02 anos (70,0mm). O recrutamento, calculado no pacote FISAT II e estimado através da presença de juvenis, mostrou-se contínuo durante todo o ano. Os métodos de análises de frequência e comprimento inseridos no pacote FISAT (Bhattacharya, ELEFAN I e Shepherd’s) não foram capazes de determinar os parâmetros de crescimento, provavelmente devido ao crescimento lento e recrutamento contínuo durante todo ano. O tamanho total da população no manguezal do CMA foi estimado em 1262 indivíduos (+- 401ind.), baseado nos dados de marcação e recaptura.
Knowledge on the growth parameters and mortality in brachyuran is fundamental to the understanding of the dynamics and management of their populations. Growth and mortality parameters were estimated for Cardisoma guanhumi Latreille, 1825 (locally known as”guaiamum”), a species with high socio-economic importance in northeastern Brazil and currently considered by the Ministry of the Environment as Critically Endangered of Extinction. The samples were taken over one year, from April 2015 to March 2016, at the upper margin of a small, isolated mangrove patch at CMA-ICMBio-CEPENE on Itamaracá Island, Pernambuco, Brazil. A total of 1078 individuals (572 males and 506 females) were captured, measured and weighed. Of these, 291 individuals were marked with PIT tags (Passive Integrated Transponder tags), as to determine the growth parameters through the analysis of the increments in weight and size and individual growth. For the data analysis, we used the ELEFAN I method (based on the frequency distribution of carapace width 1078 individuals), inserted into the computer package FISAT II and through the GrowthTraject function (based on individual increments of 291 individuals marked with PIT tags, using the fishmethods package ("R” Environment). C. guanhumi showed carapace widths between 20.9 and 70.0 mm (mean: 43,45 mm, standard deviation: 8,53 mm, median: 44,05 mm) and total weight between 4 and 162 g (mean: 45,85 g, standard deviation: 25,34 g, median: 44,0 g). There were no significant differences in average size and average weight between males and females. Growth parameters estimated with the fishmethods package, based on 130 increments (males and females), were: L∞ (asymptotic carapace width) = 108.03 mm; K (coefficient growth) = 0.145 y-1. Total mortality (Z) of the population, estimated through the Length-converted catch Curve method (FISAT II package), using the fishmethods growth parameters, was 2.39 y-1. Since this is a restricted area without regular commercial catches, so this value is roughly equivalent to the total and natural mortality (Z = M). The age of the individuals captured ranged from 1.49 years (20,9 mm) to 7.02 years (70,0 mm). Recruitment, calculated in FISAT II package and estimated by the presence of juveniles, showed to be continuous throughout the year. The methods of length-frequency analysis inserted in the FISAT package (Bhattachary of protective measures for this species.
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5

Birch, W. J. "Incremental growth of deciduous tooth enamel." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1348309/.

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Deciduous tooth formation begins before birth and ends after birth. This makes it more difficult to construct a continuous developmental chronology for deciduous teeth than for permanent teeth. The discovery of the neonatal line in enamel and confirmation that it marks birth, allowed the expansion of deciduous dental chronologies, which until this time had been largely based on qualitative descriptions. The aim of this study was to use the daily incremental record in deciduous enamel to document rates of enamel formation and to use these data to produce regression equations that describe the average rates of deciduous enamel formation for each tooth type. These formulae can then be applied to all deciduous teeth even when daily increments are not visible, in order to estimate crown formation times and other events during crown development, as well as to determine the age at death where enamel formation has ceased prior to completion. In permanent teeth, rates of enamel formation vary between 2.5μm per day at the EDJ to 6.5μm per day at the enamel surface. Seventy deciduous ground sections were examined and it was established that the daily rates in deciduous enamel varied less, with regional weighted means for all tooth types ranging from 2.85μm per day at the EDJ to 3.40μm per day at the enamel surface with extreme outliers of 2.07 to 4.97μm per day. The average daily incremental growth rate of enamel in deciduous teeth was calculated for each tooth type, the weighted mean of the apposition rate over both aspects (labial/buccal and lingual) and over all three regions (cervical, lateral and occlusal) for all tooth types was 3.23μm per day. A key finding of this study was that there is a marked reduction in the enamel formation rate in the zone immediately following the neonatal line or following other accentuated striae assumed to be associated with stressful events. A catch-up phase usually followed these events, during which the previous rates recovered. These data provide clear evidence of enamel hypoplasia associated with both the birth process and other events that cause stress in perinatal life.
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6

Faias, Sónia Maria Marques Pacheco. "Using neighbourhood vegetation information on cork oak growth and yield modelling." Doctoral thesis, ISA, 2020. http://hdl.handle.net/10400.5/21227.

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Doutoramento em Engenharia Florestal e dos Recursos Naturais / Instituto Superior de Agronomia. Universidade de Lisboa
The present work contributes to information regarding the competition on the tree and cork growth, by evaluating the neighbourhood vegetation and local tree density impact. From a specific trial established to compare the effect on the tree of different understory management options, along a cork rotation cycle of 9 years, cork samples were taken at the beginning and at the end of the cycle on trees within lagged cycles. Former results revealed no effect on cork annual growth and wood increment for the trees growing under lupine periodical seeding. When analysing the interaction between cork ring age and understory operations, different thresholds were linked to the shrubs’ maintenance and the lupine seeding. Later, this trial was monitored to compare the shrubs’ maintenance versus removal with or without NP soil fertilization. On the set of selected trees, diameter increment was monthly monitored, as well as, leaves nutrients seasonal variability, and differences were found in the treatment with soil fertilization. Data gathered from a Portuguese network of permanent plots across the cork oak species distribution area was used to model tree variables including the site characteristics. Focusing the analysis on young plantations and never debarked stands, the relationship of the diameter relative growth rate over tree dimension showed signs of inter-tree competition before the first cork extraction in older high-density stands. A crown width model developed with a fixed-effect approach was applied using national forest inventory datasets. Subsequently, a decrease in crown cover was identified in Portugal over ten years. Using the Portuguese dataset with a Spanish dataset, a diameter increment model was developed applying two methodologies: age-independent difference equations and potential growth times a modifier. This Iberian dataset allowed testing the inclusion of stand variability associated with climate and soil site conditions
O presente trabalho contribui com informação sobre competição, avaliando o impacto da vegetação vizinha e da sua densidade, no crescimento da árvore e da cortiça. Para comparar o efeito na árvore da gestão do subcoberto, durante um ciclo de descortiçamento (9 anos), foram recolhidas amostras de cortiça, no início e final do ciclo, em árvores sujeitas a ciclos desfasados num ensaio específico. Primeiramente não foi encontrado efeito no crescimento anual da cortiça e no incremento em madeira entre árvores sujeitas a diferente gestão. Mas analisando a interação entre a idade do anel de cortiça e as operações realizadas, foram associados diferentes limites à manutenção dos arbustos e à sementeira de tremocilha. Este ensaio foi continuado para comparar a manutenção com a remoção dos arbustos, com ou sem fertilização NP do solo, monitorizando um conjunto de árvores selecionadas. Analisando o registo do incremento em diâmetro mensal e da variabilidade sazonal dos nutrientes das folhas, foram encontradas diferenças no tratamento com fertilização do solo. Os dados recolhidos numa rede de parcelas permanentes localizadas na área de distribuição de sobreiro em Portugal, foram utilizados para analisar e modelar variáveis arbóreas. Abordando apenas dados de plantações jovens e povoamentos não descortiçados, a relação entre a taxa de crescimento relativo em diâmetro com a dimensão da árvore mostrou sinais de competição nas árvores não descortiçadas, em povoamentos adultos de elevada densidade. Foi desenvolvido um modelo predição do diâmetro da copa que aplicado aos dados do inventário florestal nacional, indicaram uma diminuição da percentagem de coberto, num horizonte de dez anos. Juntando a este conjunto, dados de parcelas espanholas, foi desenvolvido um modelo para o incremento em diâmetro, com a inclusão da variabilidade local associada ao clima e ao solo, abordando duas metodologias: equações às diferenças independentes da idade e potencial de crescimento multiplicando um modificador
N/A
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7

Schöpa, Anne K. "Incremental pluton growth : building of large magma chambers." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.633111.

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Numerical models of conductive heat flow have been used to explore the connection between incremental pluton growth and large magma chambers. The simulations include repeated sill injections of melt into the crust using variable repose times in between these injections. Adopting this novel approach of a changing magma flux during the emplacement time of a pluton, different intrusion scenarios are tested to constrain the conditions for melt accumulation in the crust during progressive pluton growth. Results reveal that only a rapid increase in magma flux above a background value representative for plutons can lead to the formation of magma reservoirs. Field observations, image analysis (lA) with the intercept method and an anisotropy of magnetic susceptibility (AMS) study are conducted in the silicic Lago della Vacca Complex (LVC) in the Adamello Batholith, northern Italy, to gain insight into magmatic and magnetic fabrics. Combining this data enabled a detailed emplacement scenario for the LVC to be developed. Furthermore, a comparison between the results of lA and AMS shows that these methods are consistent, thus emphasising the applicability of lA and AMS in silicic rocks to reconstruct intrusion emplacement. This is the first comprehensive comparison between AMS and mineral fabrics, obtained by field measurements, lA and computer-assisted X-ray micro-tomography (X-ray /LCT) of which we are aware. The X-ray /LCT images provide the base to acquire the shape-preferred orientation (Spa) of magnetites and mafic silicates, and the spatial distribution of magnetites in a sample. Results show that the AMS signal is consistent with the spa of magnetite grains and clusters but differs from the distribution of the magnetites, suggesting that the AMS is controlled by magnetite grain shape. Moreover, the AMS agrees with the field measurements, lA and the spa of the mafic silicates underlining that lA and AMS can be applied to characterise fabrics in ferromagnetic granitoids. III
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8

Portela, Artur. "Dual boundary element incremental analysis of crack growth." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294007.

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9

Xavier, Talita Miranda Teixeira. "Efeito da restrição hídrica sobre o crescimento de clones de eucalipto." Universidade Federal do Espírito Santo, 2010. http://repositorio.ufes.br/handle/10/6625.

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The establishment and early field grown of forest tree species are strongly affected by the availability of soil water and planting season. The aim of this work was to study the impact of soil water stress on growth of young plants of two hybrid clones of Eucalyptus grandis x E. urophylla, both subjected to 4 levels of water deficit at two planting dates. The study was conducted in the Experimental Field Station of the Center for Research and Dissemination of Technology in Forestry, Water Resources and Sustainable Agriculture (NEDTEC), the Center for Agrarian Sciences, Federal University of Espírito Santo (CCA-UFES), located in Jerônimo Monteiro, Espirito Santo State. The study was conducted in two seasons, the first being the period from February 9 to June 9, 2009 and the second from July 11 to November 7, 2009. In both seasons, meteorological data were measured including global and photosynthetic ative radiation, vapor pressure deficit, air temperature, air relative humidity and wind speed. The experimental design was a random split plot 2 x 4, allocating the 4 levels of water deficits in the main plots and subplots 2 times, with three replications. The water management strategies were applied: Deficit 0 (D0) no deficit, Deficit 1 (D1) cut irrigation at 30 days of experiment, remaining dry until the end of the experiment, Deficit 2 (D2) cut irrigation at 30 days of experiment, suspension irrigation for 60 days and subsequent restart of irrigation for 30 days; Deficit 3 (D3) cut irrigation at 60 days of experiment, continuing until the end of the experiment. The experimental data were subjected to analysis of variance and when significant, the means were compared using the Tukey average at 5% probability for each clone. With this study was possible to assess the impact of different levels of soil water deficit in the initial growth of plants in two seasons and assess the increase in plant dry biomass alocation during treatment application with samples taken from averages of each deficit every 30 days. The variables measured in both experiments were: total plant height, stem diameter, number of leaves, total leaf area, leaf dry weight, stem and branches dry weight , root dry mass and total plant dry weight. Climatic variables were evaluated throughout the experimental period, the two periods to determine the weather conditions in each season. For the two clones in general, water deficits promoted the reduction of the morphological variables studied and the experimental time was the factor that most influenced the reduction of plant growth. The season 1 was the one that provided superior results, and season 2 was the most adversely affected plant growth significantly reducing all morphological deficits in all water, including the D0
O estabelecimento e o crescimento inicial de espécies florestais no campo são fortemente afetados pela disponibilidade de água no solo e pela época de plantio, por isso, o presente trabalho estuda o impacto do déficit hídrico no crescimento de mudas de dois clones do híbrido Eucalyptus grandis x Eucalyptus urophylla, ambos submetidos a 4 níveis de déficit hídrico, em duas épocas de plantio. O estudo foi realizado na área experimental do Núcleo de Estudos e Difusão de Tecnologia em Florestas, Recursos Hídricos e Agricultura Sustentável (NEDTEC), do Centro de Ciências Agrárias da Universidade Federal do Espírito Santo (CCA-UFES), localizado no município de Jerônimo Monteiro. O trabalho foi realizado em duas épocas distintas, sendo a primeira no período de 09 de fevereiro a 09 de junho de 2009 e a segunda no período de 11 de julho a 07 de novembro de 2009, visando à realização das observações em diferentes condições de regime de radiação, déficit de pressão do vapor do ar, temperatura, umidade relativa do ar e velocidade do vento. O delineamento experimental utilizado foi o inteiramente ao acaso em parcelas subdivididas 2 x 4, alocando-se os 4 níveis de déficits hídricos na parcela principal e as 2 épocas nas subparcelas, com três repetições. Os manejos hídricos aplicados foram: Déficit 0 (D0) sem déficit, Déficit 1(D1) corte da irrigação aos 30 dias de experimentação, permanecendo até o final do experimento, Déficit 2 (D2) corte da irrigação aos 30 dias de experimentação, suspensão da irrigação por 60 dias e posterior retomada da irrigação por mais 30 dias; Déficit 3 (D3) corte da irrigação aos 60 dias de experimentação, prolongando até o final do experimento. Os dados experimentais foram submetidos à análise de variância, e quando significativas, as médias foram comparadas pelo teste de média Tukey a 5% de probabilidade, para cada clone estudado. Com este trabalho, foi possível avaliar o impacto de diferentes déficits hídricos, no crescimento inicial das plantas, em duas épocas do ano e avaliar o incremento no desenvolvimento das plantas durante a aplicação dos tratamentos, com retiradas de amostras médias de cada tratamento a cada 30 dias. As variáveis medidas nos dois experimentos foram altura total da planta, diâmetro ao nível do coleto, número de folhas, área foliar, matéria seca de folhas, matéria seca de haste e ramos, matéria seca de raízes e matéria seca total. Foram avaliadas as variáveis climáticas durante todo o período experimental, nas duas épocas, a fim de determinar a condição do clima em cada época. Para os dois clones estudados, em geral, os déficits hídricos promoveram a redução das variáveis morfológicas estudadas e a época experimental foi o fator que mais influenciou a redução do crescimento das plantas. Sendo que a Época 1 foi a que proporcionou resultados superiores, e a Época 2 foi a que prejudicou mais o desenvolvimento das plantas, reduzindo significativamente todas as variáveis morfológicas em todos os déficits hídricos, inclusive o D0
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Yamaguchi, David K., and F. Craig Brunstein. "Special Sanding Films and Sandpapers for Surfacing Narrow-Ring Increment Cores." Tree-Ring Society, 1991. http://hdl.handle.net/10150/262318.

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Special sanding films (400 grit to 23 micron) and fine sandpapers (1200-1500 grit) can be used to surface increment cores containing narrow rings (e.g., >50 rings per cm) so that rings are clearly visible for microscopy and photography.
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11

Velayutham, Prematha. "From top structure to home incremental growth of subsidised housing in Mamelodi /." Pretoria : [s.n.], 2005. http://upetd.up.ac.za/thesis/available/etd-03282007-134221.

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Velayutham, Prematha. "From top structure to home :incremental growth of subsidised housing in Mamelodi." Diss., University of Pretoria, 2004. http://hdl.handle.net/2263/23522.

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13

Segal, Martin Daniel. "An Incremental Approach to Development at Gesundheit! Institute." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/30785.

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This thesis is an evaluation and proposal for development for an alternative health care center in West Virginia. The Gesundheit Institute is based on the work of Dr. Hunter "Patch" Adams and his desire to create an alternative to the current model of health care. The Institute would not charge for services and will offer non-traditional as well as traditional methods of healing. By evaluating what is currently happening at the center and what the resources are, I propose to use an incremental approach to growth. The ideas would result in a series of smaller buildings developed over time as opposed to a single larger building. The thesis includes the design for the next major building, a community center/dining hall and a basic design for a series of sleeping quarters. It also includes the reworking of the master plan to better include issues integrating incremental growth and sustainable development.
Master of Architecture
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14

Chassot, Tatiane. "Densidade e incremento diamétrico de árvores individuais da floresta ombrófila mista." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/3772.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
This study aimed to provide answers about the diameter growth for individual trees of different layers of the Mixed Ombrophylous Forest of São Francisco de Paula, in northeastern Rio Grande do Sul, as well as present methods of determining the density considering angular sampling methods. Therefore, were used 8 years remeasurements of 262 Araucaria angustifolia individuals, 111 Blepharocalix salicifolius individuals, 115 Cryptocaria aschersoniana individuals and 154 Casearia decandra individuals, sampled in the permanent plots of the Project PELD CNPq. Using angular counting methods, the density point was determined, in basal area and number of trees per hectare, in each location point of the studied species and evaluated its influence on the growth of these individuals. Proceeded a detailed analysis of the dimensional characteristics and competition for each species. Using correlation analysis, covariance and regression, increment models were adjusted, stratified by the highest correlation with the diameter increment. Was used the annual periodic increment, calculated based on the diameter increment of the individuals in the analyzed period. Generally, the point density showed a significant effect on the increment in diameter. The methodology for calculating the number of trees per hectare more correlated with the increase in diameter was Linares and Zagoya. Models resulted in good estimates of the increase, however, showed wastes with a strong tendency. The inefficiency of models can be attributed to the little distinction between the variables in each of the stratifications. For individuals of Araucaria angustifolia and Blepharocalix salicifolius was possible to stratify the individuals by diameter class. As for the Cryptocaria aschersoniana and Casearia decandra, there was a value tendency stratification. For each species at each of the stratifications, different variables had an effect on the increment of diameter with total height, a variable influence on the growth of all individuals studied. The site features of the species showed no explanatory distinctions of the increment.
Este trabalho teve como objetivo fornecer respostas sobre o crescimento em diâmetro para árvores individuais de diferentes estratos da Floresta Ombrófila Mista da Floresta Nacional de São Francisco de Paula, no nordeste do Rio Grande do Sul, bem como, apresentar metodologias de determinação da densidade considerando métodos de amostragem angular. Para tanto, foram utilizadas remedições de 8 anos de 262 indivíduos de Araucaria angustifolia, 111 indivíduos de Blepharocalix salicifolius, 115 indivíduos de Cryptocaria aschersoniana e 154 indivíduos de Casearia decandra, amostradas nas parcelas permanentes do Projeto PELD CNPq. Utilizando métodos de contagem angular, foi determinada a densidade pontual, em área basal e número de árvores por hectare, em cada ponto de localização das espécies estudadas e avaliada a sua influência sobre o crescimento desses indivíduos. Procedeu-se a uma análise detalhada das características dimensionais e de concorrência de cada uma das espécies. Utilizando análise de correlação, covariância e regressão, foram ajustados modelos de incremento, estratificados em função da variável de maior correlação com o incremento em diâmetro. Foi utilizado o incremento periódico anual, calculado com base no incremento em diâmetro dos indivíduos no período analisado. De maneira geral, a densidade pontual mostrou efeito sobre o incremento em diâmetro. A metodologia para o cálculo do número de árvores por hectare mais correlacionada com o incremento em diâmetro foi a de Linares e Zagoya. Os modelos resultaram em boas estimativas do incremento, no entanto, apresentaram resíduos com forte tendência. A ineficiência dos modelos pode ser atribuída a pouca distinção entre as variáveis em cada uma das estratificações. Para os indivíduos de Araucaria angustifolia e Blepharocalix salicifolius foi possível a estratificação dos indivíduos por classe de diâmetro. Já para a Cryptocaria aschersoniana e Casearia decandra, realizou-se uma estratificação por tendência de valorização. Para cada espécie, em cada uma das estratificações, diferentes variáveis exerceram efeito sobre o incremento em diâmetro sendo a altura total, uma variável de influência sobre o crescimento de todos os indivíduos estudados. As características de local das espécies não mostraram distinções explicativas do incremento.
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15

Houk, Stephen D. "Growh Increment Analysis of Marine Bivalves from the North Coast of Peru." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/HoukSD2002.pdf.

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16

Renzetti, Marta. "Growth Potential and Excess Returns : The Role of Incremental R&D expenditures." Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.516780.

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17

Milner, Nicky. "Incremental growth of the European oyster Ostrea edulis seasonality information from Danish kitchenmiddens /." Oxford, England : Archaeopress, 2002. http://books.google.com/books?id=nC9mAAAAMAAJ.

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18

Al-Murayati, Haider. "Diversity of the bacterial community and secondary sexual characters in the peacock." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS096/document.

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Les plumes d'oiseaux abritent de nombreux microorganismes qui pourraient être acquis dans l'environnement, ces microorganismes pouvant exercer une sélection intense sur leurs hôtes en réduisant leur fécondité et leur survie. Plusieurs taxons bactériens qui vivent sur des plumes ont la capacité de dégrader la kératine des plumes et causent des dommages à leur structure et peuvent modifier aussi leur coloration. Les oiseaux utilisent des signaux visuels tels que des couleurs vives ou des ornementations exagérées pour la communication socio-sexuelle ainsi que la reconnaissance des espèces. Seuls les individus en bonne santé sont capables de produire des caractères sexuels secondaires exagérés et restent résistants aux parasites débilitants. Le paon (Pavo cristatus) est une espèce polygame qui a plusieurs décorations exagérées, les caractères sexuels secondaires les plus remarquables du paon sont leur traîne décorée avec des ocelles magnifiques qui contiennent trois couleurs irisées différentes. Grâce à une technique basée sur la culture, j'ai isolé la communauté bactérienne des plumes de différentes parties colorées des ocelles de la traîne du paon. L'étude révèle qu'il y a eu une répartition hétérogène des bactéries parmi les différentes parties colorées des ocelles. L'abondance et la prévalence des taxa bactériens spécifiques étaient liées au degré de dégradation des plumes, à l'expression de différents caractères sexuels secondaires, à des changements dans la coloration des ocelles et à l'augmentation de la croissance quotidienne des plumes. En outre, nous avons constaté un petit effet de l'expression de caractères sexuels secondaires sur la proportion sexuelle des couvées avec un biais en faveur des individus masculins. Les travaux présentés dans cette thèse fournissent des preuves que les ocelles de plumes peuvent être considérés comme un signal fiable de la diversité et de l'abondance de bactéries chez le paon. En conséquence, ils représentent une indication pour la qualité individuelle, ce qui permet aux femelles de choisir des mâles avec une communauté bactérienne spécifique
Bird feathers harbour numerous microorganisms that could be acquired from the surrounding environment, these microorganisms may exert intense selection on their hosts by reducing fecundity and survivorship. Several bacterial taxa that live on feathers have the ability to degrade feather keratin and cause damage to feather structure and may alter the feather colouration. Birds use visual signals such as bright colours or exaggerated ornamentation for socio-sexual communication as well as species recognition. Only healthy individuals are able to produce exaggerated secondary sexual characters and still remain resistant to debilitating parasites. Peacocks (Pavo cristatus) is a polygamous species that have different exaggerated ornamentation, the most notable secondary sexual characters of the peacock are their long-decorated trains that comprise the magnificent ocelli which contain three different iridescent colours. Through a culture based technique we isolate feather bacterial community from differently coloured parts of the ocelli of the peacock’s train. The study reveals that there was a heterogeneous distribution of bacteria among the differently coloured parts of ocelli. The abundance and prevalence of specific bacterial taxa was related to the degree of feather degradation, expression of different secondary sexual character, changes in ocelli colouration and daily growth increment. Furthermore, we found a small effect of the expression of secondary sexual characters on biasing of brood sex ratio towards production of more sons than daughters. The work presented in this thesis provide evidence that feather ocelli may consider as a reliable signal of the diversity and the abundance of bacteria in peacock and in consequence indication for the individual quality and that allowing the choosy females to pick males with a specific bacterial community
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19

Holgén, Per. "Seedling performance, shelter tree increment and recreation values in boreal shelterwood stands /." Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5854-4.pdf.

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20

Woodall, C. W. "When Is One Core Per Tree Suffifcient To Characterize Stand Attributes? Results Of A Pinus Ponderosa Case Study." Tree-Ring Society, 2008. http://hdl.handle.net/10150/622568.

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Increment cores are invaluable for assessing tree attributes such as inside bark diameter, radial growth, and sapwood area. However, because trees accrue growth and sapwood unevenly around their pith, tree attributes derived from one increment core may not provide sufficient precision for forest management/research activities. To assess the variability in a tree’s inside bark radius, sapwood radius, and 10-year radial growth estimated by tree cores, two increment cores at 90 degree angles were collected from ponderosa pine (Pinus ponderosa) trees in eastern Montana (n = 2,156). Paired core measurements varied substantially with 13% mean difference for inside bark radius, 19% mean difference for sapwood radius, and 23% mean difference for estimates of radial increment. Furthermore, decreasing crown ratio, decreasing diameter, and increasing site slope were all found to increase differences in estimates derived from paired cores. Whether for management or research purposes, the number of cores that should collected per tree depend on a stand’s susceptibility to reaction wood, required measurement precision, and budgetary constraints.
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21

Milner, Nicola Jane. "Seasonality information from the incremental growth of the European oyster for Ertebølle sites in Denmark." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624124.

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22

Herdter, Elizabeth Shea. "Growth Rates in Gulf of Mexico Red Snapper, Lutjanus campechanus, Before and After the Deepwater Horizon Blowout." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5419.

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The Deepwater Horizon blowout occurred on April 20th, 2010 and released nearly 5 million barrels of crude oil into the northern Gulf of Mexico causing pollution of the water and sediment inhabited by many fishes for at least 87 days while the wellhead went uncapped. Populations of the Gulf of Mexico Red snapper, Lutjanus campechanus, an important fish to the ecology and economy in the region, exhibit affinity to shallow water oil infrastructure such as the Deepwater Horizon making them especially vulnerable to crude oil contamination. The objective of this study is to determine growth of Red snapper before, during and after the DWH spill and to assess factors potentially explaining such growth variation. Sagittal otoliths were collected from individuals sampled in 2011 - 2013 from scientific, demersal long-line surveys in the northern Gulf of Mexico (GoM) and West Florida Shelf (WFS). Age and otolith increment width analyses were performed. No annual variation in von Bertalanffy growth parameters was determined among the three catch years. The L∞ , K and t0 estimated from the complete data set (2011-2013) were 82.91, 0.20 and 0.43, respectively. However, significant differences in otolith increment width-at-age were observed in increment numbers three - seven in years following the DWH event, with declines of 13%, 15% and 22% occurring in the fourth -sixth increments. To asses the potential significance of exogenous environmental variables to observed yearly growth variation I evaluated five parameters - meridional (V) winds, zonal (U) winds, wind stress curl which is a measure of upwelling, Mississippi River discharge, and mean sea level anomaly - using a linear mixed effects model. Hypothesis testing via reduced maximum likelihood estimates indicated that variation in U winds and River discharge could significantly explain the variation in increment width. However, further work must be done in order to determine the natural, inter-annual variability in age specific growth before the results from model fitting can be considered conclusive. Mean back-calculated weight-at-age measurements were obtained in order to assess potential variation in productivity changes. Results from forward difference and reverse helmert contrast-coding indicated that weight at age three+, four+ and five+ declined by 16%, 15% and 11% in 2010, respectively. These analyses indicate a significant decline in fish growth in 2010 coincident with the DWH event, followed by a return to pre-spill rates.
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23

Lindner, Gerard Eckard. "Development of potential height growth and diameter increment models for the parameterisation of an individual tree growth model for Pinus elliottii plantations in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86621.

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Thesis (MScFor)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Individual tree models, as opposed to stand models, have the potential to greatly improve sensitivity of forest growth models to changing conditions such as silvicultural amendments, irregular stand structures, etc. It was the purpose of this study to extend two sub-components of a European individual tree growth model to introduce individual tree growth modelling concepts in South Africa using Pinus elliottii as a study species. Two main objectives were established: Modelling the potential height of stands across different site qualities and modelling diameter increment using a potential modifier approach with a combination of competition indices that change in importance according to the edaphic conditions of the site. Potential height modelling used three steps in order to achieve this objective. The first was to compare site index models based on different model fitting techniques, namely nonlinear least squares, generalised nonlinear least squares and nonlinear mixed effects models. The nonlinear mixed effects model proved to be superior in terms of achieving the principles of regression assumptions and model fit for the data range observed. The second step was to fit potential height using nonlinear quantile regression on observed spacing trial height measurements. This proved to be a robust technique able to capture potentials according to the defined Chapman-Richards model structure. The final step was to use the predicted site index as a site classification variable in order to predict potential height. While some small deviation occurred, potential height seems to be well correlated to site index and validation on selected sites suggested that site index can be used to model potential height until a more sophisticated site classification model is used for future improvement of the model. Diameter increment modelling followed six major steps in order to apply the full parameterisation methodology of an age-independent diameter increment model dependent on tree diameter and competition. Diameter increment potentials were fit using site index as a predictor of the potential height curves. Multiple competition indices were tested on two sites to obtain a combination of two indices, which can capture overtopping and local crowding effects. Principle components analysis and variance inflation factors calculation were applied to test for collinearity between indices. Suitable combinations were tested resulting in a combination of the KKL and Local Basal Area competition indices. Changing importance of the two indices were observed on the two sites tested indicating a shift in the mode of competition according to a water gradient. These were combined in a deterministic potential modifier model, which mimicked competitive stages over age; however the validation showed a skewed distribution, which was not sensitive to stand density gradients. A stochastic model was constructed to model variance from observed residual plots using linear quantile regression to determine bounds for a truncated normal distribution which generates random deviates for a predicted increment. The stochastic element significantly improved the performance and sensitivity of the model, however the model was still not sensitive enough at very high and very low spacing densities. All in all two key models for an adaptation of an individual tree growth simulator to South African conditions were successfully demonstrated. The two main objectives were achieved; however some indicated improvements could be made, especially for the competition indices where the sensitivity of competition to changing resource limitation according to site and temporal scales needs to be further investigated. Furthermore, the full set of models for simulating individual tree growth still needs to be applied. Overall, as a methodological approach, the study outlined problems and future improvements, introduced new concepts and can serve as a guideline for future parameterisation of an individual tree growth model.
AFRIKAANSE OPSOMMING: In vergelyking met vakgroeimodelle, het individuele-boomgroeimodelle die potensiaal om die sensitiwiteit van plantasiegroeimodelle vir veranderende omstandighede soos aanpassings in boskultuur, onreëlmatige vakstrukture, ensovoorts, drasties te verbeter. Die doel van hierdie studie was om twee subkomponente van ‘n Europese individuele-boomgroeimodel uit te brei om sodoende individuele-boomgroei modelleringskonsepte in Suid-Afrika bekend te stel. Pinus elliottii is gebruik as studiespesie. Twee hoofdoelstellings is bepaal. Eerstens, die modellering van hoogtegroei potensiaal van opstande oor verskeie vlakke van groeiplek kwaliteit. Tweedens, die modellering van deursnee-aanwas deur gebruik te maak van ‘n potensiaal matigingsbenadering “potential modifier approach“ met ‘n kombinasie van kompetisie-indekse waarvan die belangrikheid verander volgens die edafiese toestande van die groeiplek. Die hoogtepotensiaalmodellering bestaan uit drie stappe. Tydens die eerste stap word groeiplek bonniteitsmodelle vergelyk op grond van verskillende modelpassingstegnieke, naamlik nie-lineêre minimum kwadrate, algemene nie-lineêre minimum kwadrate en nie-lineêre gemengde effek modelle. Laasgenoemde het die beste gevaar in terme van die beginsels van regressiemodelle asook die mate waarin die model die waargeneemde data pas. Tweedens is hoogtegroei potensiaal gemodelleer deur nie-lineêre kwantielregressie op waargeneemde hoogtes van spasiëringseksperimente toe te pas. Die metode is robuust en in staat om potensiale volgens die gedefinieerde Chapman Richards modelstruktuur vas te vang. Laastens is die voorspelde bonniteits indeks as ‘n groeiplek klassifasie veranderlike gebruik om sodoende die hoogtegroei potensiaal te voorspel. Alhoewel klein afwykings voorgekom het, blyk hoogtegroei potensiaal goed gekorreleer te wees met bonniteits indeks. Uit validasie op geselekteerde groieplekke blyk dit dat bonniteits indeks gebruik kan word om hoogtegroei potensiaal te modelleer totdat ‘n meer gesofistikeerde groeiplek klassifikasiemodel beskikbaar is wat die model verder sal kan vebeter. Die volledige parametriseringsmetodiek van ‘n ouderdoms-onafhanklike deursnee-aanwas model wat afhanklik is van boomdeursnee en kompetisie bestaan uit ses hoof prosesse. Nie-lineêre kwantielregressie is gebruik om deursnee-aanwaspotensiale te pas vir verskeie groeiplekke. Dié is gekombineer met ‘n bonniteits indeks om ‘n nuwe model te vorm waarmee hoogtegroeipotensiaal kurwes voorpel kon word. Daar is met veelvuldige kompetisie-indekse op twee groeiplekke geëksperimenteer om ‘n kombinasie van slegs twee indekse te vind wat die effekte van oorskaduwing en plaaslike verdringing kan vasvang, te vind. Hoof komponent analise “Principle components analysis” en variansie inflasie faktore berekening “variance inflation factors calculation” is gebruik om vir kollineariteit tussen die indekse te toets. Gepaste indekskombinasies is getoets. ‘n Kombinasie van die KKL en plaaslike basale oppervlakte “Local Basal Area” kompetisie-indekse het die beste resultate gelewer. Die twee indekse is as volg geselekteer. Veranderings in die belangrikheid van elk van die indekse is waargeneem op die twee toetspersele. Dit dui op ‘n verskuiwing in die modus van kompetisie afhangend van ‘n watergradiënt. Die twee indekse is gekombineer in ‘n deterministiese potensiaal matigings model wat die kompeterende stadiums oor ouderdom naboots. Validasie het egter ‘n skewe verdeling wat nie sensitief vir opstandsdigtheidsgradiënte is nie, gewys. ‘n Stogastiese model is ontwikkel om variansie in die residuele grafieke te modelleer. Lineêre kwantielregressie is gebruik om grense vir ‘n afgestompte normaalverdeling wat ewekansige afwykings vir ‘n voorspelde aanwas te bepaal. Die stogastiese element het die prestasie van die deterministiese model merkbaar verbeter. Selfs met die stogastiese element, is die model egter steeds nie sensitief genoeg vir baie hoë en baie lae opstandsdigthede nie. Ter opsomming is twee modelle vir ‘n aanpassing van ‘n individuele-boomgroeisimuleerder vir Suid- Afrikaanse toestande suksesvol gedemonstreer. Die twee hoofdoelstellings is bereik. Daar is egter steeds ‘n paar aangeduide verbeterings wat aangebring kan word. Die sensitiwiteit van die kompetisie-indekse op hulpbronbeperkings wat verander op grond van die ruimtelike en temporale skale moet veral verder bestudeer word. Verder moet die volle stel modelle wat benodig word om individuele-boomgroei te modelleer nog toegepas word. As ‘n metodologiese benadering, het die studie probleme uitgewys en toekomstige verbeterings aangedui, nuwe konsepte bekendgestel en kan dus dien as ‘n riglyn vir toekomstige parametrisering van individuele-boomgroeimodelle.
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24

Souza, Luis Henrique da Silva. "INCREMENTO VOLUMÉTRICO DE Nectandra megapotamica (Spreng.) Mez EM FLORESTA OMBRÓFILA MISTA." Universidade Federal de Santa Maria, 2005. http://repositorio.ufsm.br/handle/1/8633.

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At the present work it was studied growing of Nectandra megapotamica (Spreng.) Mez species, through a sampler compounded by 11 dominant trees selected from rainforest in Nova Prata borrough, state of Rio Grande do Sul. The growth of the sampler trees can be give up successfully through steam analysis determ the growth trend in percentual volume along time, for the selected trees. The mathematical model better represents the growth trend in percentual volume was described as iv%=(b0+b1.ln dap)2, fitting individually per tree. Covariance analysis earn possible to cluster three groups, contends trees with decreasing trend were similar in relationship to trend and curves level, being possible to describe this variations with mathematical models using independent factors, as: morphomety, competition and environmental from the trees in case, by expressions : b1 = 0,41738583 + 4,16179208.id5 - 6,29332107.h/d + 0,37822636.EXPOS - 0,11519372.Ir + 5,80418708.BALcor 0,06858050.Lc, with determination coefficient equal to 0,9979 and variation coefficient of 1,73%, as well as the differences between curves levels by equation b0 = 2,62465943 13,37023979.id5 + 22, 08329412.h/d 1,33160878. EXPOS + 0,34688547.Ir 23,88899208.BALcor + 0,25692291.Lc, with determination coefficient fitting on 0,9907 and variation coefficient of 2,71%.
No presente trabalho, foi estudado o crescimento da espécie Nectandra megapotamica (Spreng.) Mez através de uma amostra composta por 11 árvores dominantes, selecionadas em Floresta Ombrófila Mista, no município de Nova Prata-RS. O crescimento das árvores amostradas pôde ser reconstituído com sucesso por meio da análise de tronco, determinandose a tendência do crescimento em volume percentual ao longo do tempo, para as árvores selecionadas. O modelo matemático que melhor representou a tendência de crescimento em volume percentual foi descrito como iv%=(b0+b1.ln dap)2, ajustado por árvore individual. A análise de covariância possibilitou a formação de três grupos contendo árvores com tendência decrescente semelhantes entre si, em relação à tendência e nível das curvas. Tornou-se possível descrever estas variações com modelos matemáticos utilizando-se variáveis independentes de morfometria, concorrência e ambientais, das árvores estudadas, pelas expressões: b1 = 0,41738583 + 4,16179208.id5 - 6,29332107.h/d + 0,37822636.EXPOS - 0,11519372.Ir + 5,80418708.BALcor 0,06858050.Lc, com coeficiente de determinação ajustado igual a 0,9979 e coeficiente de variação de 1,73%, bem como as diferenças entre níveis das curvas pela equação b0 = 2,62465943 13,37023979.id5 + 22,08329412.h/d 1,33160878.EXPOS + 0,34688547.Ir 23,88899208.BALcor + 0,25692291.Lc, com coeficiente de determinação ajustado de 0,9907 e coeficiente de variação igual a 2,71%.
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25

Allen, II Micky Gale. "Stand Density Management for Optimal Volume Production." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/71825.

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The relationship between volume production and stand density, often termed the 'growth-density relationship', has been studied since the beginnings of forestry and yet no conclusive evidence about a general pattern has been established. Throughout the literature claims and counterclaims concerning the growth-density relationship can be found. Different conclusions have been attributed to the diverse range of definitions of volume and stand density among problems with study design and other pitfalls. Using data from two thinning studies representing non-intensively and intensively managed plantations, one spacing trial, and one thinning experiment a comprehensive analysis was performed to examine the growth-density relationship in loblolly pine. Volume production was defined as either gross or net periodic annual increment of total, pulpwood, or sawtimber volume. These definitions of volume production were then related to seven measures of stand density including the number of stems per hectare, basal area per hectare, two measures relative spacing and three measures of stand density index. A generalized exponential and power type function was used to test the hypothesis that volume production follows either an increasing or unimodal pattern with stand density. These patterns were tested using all combinations of the six definitions of volume production and the seven measures of stand density. Significance of the parameters indicated that different patterns existed depending on the type of management (intensive vs. non-intensive), if thinning is performed, and depending on the definitions of growth and density. The growth-density pattern was generally the same between gross and net production although different patterns emerged when comparing total, pulpwood, and sawtimber volumes. The definitions of stand density which used diameter as a measure of average tree size were more highly correlated with volume production and produced similar patterns while the number of stems per hectare was the least correlated. Further analysis was performed to evaluate Langsaeter's hypothesis which states that volume production is constant and optimal across a wide range of stocking. A mixed-model approach was used to test the equality in mean volume production across a range of planting densities and thinning intensities. To account for the effects of age, the equality in mean volume production was tested separately across a range of ages from 8 to 25 years within the spacing trial data and across a range of one to six years since thinning within the thinning experiment. A multiple comparison test indicate that pattern of volume production and stocking is highly related to the two stages of self-thinning. In young stands, within the distance-independent mortality stage, volume production increases with increasing planting density and therefor increasing stocking. During the distance-dependent mortality stage the assumption of constant and optimal volume production across a wide range of stocking is generally correct. However when mortality began to reduce canopy closure to the point that the residual stand could not recover gaps in the canopy a decline in volume production occurred resulting in a decreasing relationship with increasing stocking. Finally, a system of equations were constructed to describe volume production at the individual tree and stand levels. From this model it was determined that stand level volume production follow an increasing pattern with stand density.
Ph. D.
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26

Allen, Micky Gale II. "Stand Density Management for Optimal Volume Production." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/71825.

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The relationship between volume production and stand density, often termed the 'growth-density relationship', has been studied since the beginnings of forestry and yet no conclusive evidence about a general pattern has been established. Throughout the literature claims and counterclaims concerning the growth-density relationship can be found. Different conclusions have been attributed to the diverse range of definitions of volume and stand density among problems with study design and other pitfalls. Using data from two thinning studies representing non-intensively and intensively managed plantations, one spacing trial, and one thinning experiment a comprehensive analysis was performed to examine the growth-density relationship in loblolly pine. Volume production was defined as either gross or net periodic annual increment of total, pulpwood, or sawtimber volume. These definitions of volume production were then related to seven measures of stand density including the number of stems per hectare, basal area per hectare, two measures relative spacing and three measures of stand density index. A generalized exponential and power type function was used to test the hypothesis that volume production follows either an increasing or unimodal pattern with stand density. These patterns were tested using all combinations of the six definitions of volume production and the seven measures of stand density. Significance of the parameters indicated that different patterns existed depending on the type of management (intensive vs. non-intensive), if thinning is performed, and depending on the definitions of growth and density. The growth-density pattern was generally the same between gross and net production although different patterns emerged when comparing total, pulpwood, and sawtimber volumes. The definitions of stand density which used diameter as a measure of average tree size were more highly correlated with volume production and produced similar patterns while the number of stems per hectare was the least correlated. Further analysis was performed to evaluate Langsaeter's hypothesis which states that volume production is constant and optimal across a wide range of stocking. A mixed-model approach was used to test the equality in mean volume production across a range of planting densities and thinning intensities. To account for the effects of age, the equality in mean volume production was tested separately across a range of ages from 8 to 25 years within the spacing trial data and across a range of one to six years since thinning within the thinning experiment. A multiple comparison test indicate that pattern of volume production and stocking is highly related to the two stages of self-thinning. In young stands, within the distance-independent mortality stage, volume production increases with increasing planting density and therefor increasing stocking. During the distance-dependent mortality stage the assumption of constant and optimal volume production across a wide range of stocking is generally correct. However when mortality began to reduce canopy closure to the point that the residual stand could not recover gaps in the canopy a decline in volume production occurred resulting in a decreasing relationship with increasing stocking. Finally, a system of equations were constructed to describe volume production at the individual tree and stand levels. From this model it was determined that stand level volume production follow an increasing pattern with stand density.
Ph. D.
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27

Smith, Michael C. "Diameter and height increment and mortality functions for loblolly pine trees in thinned and unthinned plantations." Thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-03242009-040942/.

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28

Pedersen, Emil. "Impact of the Warm Summer of 2018 on Growth of Roach (Rutilus rutilus) in Lake Tåkern, Sweden." Thesis, Linköpings universitet, Biologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166635.

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Climate change will lead to higher temperatures and longer summers in the future, which will likely influence the growing season of fish living in temperate lakes. The warm summer of 2018 in Sweden matches prognoses for normal summers at the end of the century and can thus be used to investigate the effect of temperature related factors on fish growth. In this study I used back-calculation of the growth of roach (Rutilus rutilus) caught in Lake Tåkern, Sweden, to find differences in growth during 2018’s hot summer versus the period 2012-2017. I compared growth during these years with results from a similar study from Lake Tåkern in 1978. For this comparison I used 1977 as a representative year for the 1970’s. I applied sclerochronology to the scales to determine age and growth. The results show that growth in terms of length increment was faster in 2018 than in 2012 – 2016. The results indicate that 2018 had an effect on the whole roach population, since significant differences were found across age groups. Additional comparisons between 1977 and 2018 showed no significant difference. Differences in roach growth rate between 2012-2018 could be caused by the differences in mean temperature during the roaches growing season, since 2018 was abnormally warm, and the difference between 1997 and 2018 could be attributed to 1977’s fish death. This means that if the pattern of climate change continues, roach growth rates will increase in the future regardless of age group.
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29

Karlsson, Kjell. "Growth allocation and stand structure in Norway spruce stands : expected taper and diameter distribution in stands subjected to different thinning regimes /." Uppsala : Dept. of Bioenergy, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/200575.pdf.

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30

Biondi, Franco, and Fares Qeadan. "A Theory-Driven Approach To Tree-Ring Standardization: Defining The Biological Trend From Expected Basal Area Increment." Tree-Ring Society, 2008. http://hdl.handle.net/10150/622585.

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One of the main elements of dendrochronological standardization is removing the biological trend, i.e. the progressive decline of ring width along a cross-sectional radius that is caused by the corresponding increase in stem size and tree age over time. The ‘‘conservative’’ option for removing this biological trend is to fit a modified negative exponential curve (or a straight line with slope ≤ 0) to the ring-width measurements. This method is based on the assumption that, especially for open-grown and/or shade-intolerant species, annual growth rate of mature trees fluctuates around a specific level, expressed by a constant ring width. Because this method has numerical and conceptual drawbacks, we propose an alternative approach based on the assumption that constant growth is expressed by a constant basal area increment distributed over a growing surface. From this starting point, we derive a mathematical expression for the biological trend of ring width, which can be easily calculated and used for dendrochronological standardization. The proposed C-method is compared to other standardization techniques, including Regional Curve Standardization (RCS), of tree-ring width from ponderosa pines (Pinus ponderosa Douglas ex P.Lawson & C.Lawson) located at the Gus Pearson Natural Area (GPNA) in northern Arizona, USA. Master ring-index chronologies built from ring area, RCS, and C-method reproduced stand-wide patterns of tree growth at the GPNA, whereas other standardization options, including the ‘‘conservative’’ one, failed to do so. In addition, the C-method has the advantage of calculating an expected growth curve for each tree, whereas RCS is based on applying the same growth curve to all trees. In conclusion, the C-method replaces the purely empirical ‘‘conservative’’ option with a theory based approach, which is applicable to individual ring-width measurement series, does not require fitting a growth curve using nonlinear regression, and can be rigorously tested for improving tree-ring records of environmental changes.
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31

Roman-Gonzalez, Alejandro. "Investigation of shallow marine Antarctic environments using the annual increment growth pattern of the bivalve mollusc, Aequiyoldia eightsii (Jay, 1839)." Thesis, Cardiff University, 2017. http://orca.cf.ac.uk/117059/.

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The research presented here constitutes the latest advances in the use of the Antarctic bivalve mollusc Aequiyoldia eightsii as a sclerochronological proxy for Antarctic coastal waters. A. eightsii has the potential to provide annually-resolved records for the Antarctic shallow waters beyond the beginning of the instrumental record. A comprehensive study of A. eightsii shell growth was carried out, which highlighted two ontogenetic trends: i) negative exponential and ii) a quasi-cyclic trend of a period of nine years, which may relate to allocation of energetic resources. Using crossmatching techniques, four chronologies from adjacent locations near Rothera Station (West Antarctic Peninsula, WAP) and an additional chronology from historical samples collected near Signy Station (South Orkney Islands, SOIs) were developed. Additionally further work on a pre-existing chronology from the SOIs is presented. Instrumental records and climatic indices were analysed to determine environmental variability and the factors controlling shell growth. Seawater temperature and fast-ice duration seem to be the main environmental drivers of A. eightsii shell growth. Shell growth of South Cove (WAP) specimens seem to better reflect to environmental conditions recorded in the Rothera Biological Time Series. Stable oxygen and carbon isotope (δ18O and δ13C) records were developed from shell carbonate material; these showed sub- and inter-annual variability and all specimens showed similar trends in δ18Oshell and δ13Cshell, with the exception of a deep-collected specimen of the SOIs, which showed much reduced interannual variability and a stronger δ13Cshell negative trend with ontogenetic age. Additionally, stable isotope fractionation depending anatomical part of the shell (anterior, ventral and posterior) was studied, which showed intra-increment variability in δ18Oshell and δ13Cshell. The present work constitutes a comprehensive calibration of A. eightsii as a sclerochronological proxy for Antarctic shallow coastal waters, which will help to expand our understanding of climate trends in the region.
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32

Cavalli, Jean Pierre. "CARACTERIZAÇÃO E MODELAGEM DO CRESCIMENTO DA COPA E DO INCREMENTO DE ÁRVORES ISOLADAS DE Cedrela fissillis Vell." Universidade Federal de Santa Maria, 2013. http://repositorio.ufsm.br/handle/1/8716.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
On the growth evaluation of the open-grown trees was selected 57 samples, of which were mensuration many morphometric variables from digital photographs in software AutoCAD and dendrometrics variables in bole increment extracted in diameter breast height (DBH). The development of this research was to described the singular dimensions and recover crown and bole growth from open-grown Cedrela fissilis, corresponding to period 2007-2011, and build mathematical equations to described the growth of variable crown diameter (CD), mantle of the crown (MC), crown diameter in relative heights (CDrh) and periodic annual increment in basal area (PAIb). In the annual lengthening (AL) were observed minimum, maximum and median annual values of 3.0, 91.0 and 32.4 cm, respectively. As well as, serie correlations, determined by Pearson (r = 0.76 a 0.86; Pr<.0001), with higher lengthening connected to the lower orders of branching. In periodic lengthening (PL), corresponding to the period of 2007-2011 there were values of up to 1.82 m, found in diameter class 30-40, with a coefficient of variation (CV) up to 67.67%, checked in diametric class > 60. To model growth construction 35 trees were selected from 57 initially sampled considering it crown and bole conditions, having been discarded sample of the > 60 diametric class. To the mantle of the crown variable the model NLMC=b0+b1*(1/DBH)+b2*(DBH²) has good adjust (R²adj.=0.92; VC=6.12%). The equation to annual lengthening of the crown, ALC=b0+b1*(NLCAI)+b2*(DBH) showed adjustment and precision (R²adj.=0.50; VC=35.95%), it explaining until 50% total variance, but with higher percent residual. With similar precision, the model adjusted to crown growth in diameter, CGD=b0+b1*(NLCAI), had statistical precision defined to R²adj= 0.44 and VC=36.25%, with higher VC resulted from the higher variance in samples. To the CDrh the adjust was represented to R²adj.=0.58 and VC=52.41%, had been defined the model NLCDrh=b0+b1*(NLDBH)+b2*(1/hi²)+b3*(DBH²), with the results of residual evaluations didn t submit normality distribution and homogeny variance. The adjust to CAIb equation showed good statistical precision (R²adj.=0.66; VC=11%), it explaining until 66% total variance from model NLCAIb=b0+b1*(DBH)+b2*(h/d). On the increment descriptive analyses it observed high periodic annual increment in diameter (PAId) and PAIb in the 25, 35 and 45 cm diameter class. The PAId medium, minimum and maximum values correspond to 3.6 cm, 0.7 cm and 7.3 cm. At the 35 and 45 cm class it observed 95.6 and 75.5 PAIb average, respectively. All of the diameter classes it was observed current annual increment in diameter (CAId) higher 2.5 cm. The crown growth reviews from the open-grown trees demonstrated that the crown growth rhythmic and its correlation with the bole increments it turn possible to build growth models characterized to good adjust and statistical efficiency, wherever, it should be stratification methods based in site informations. The methodology analyses with digital photography also showed good precision and practicality, it can be widely used to review singular and open-grown trees.
Na avaliação do crescimento de árvores isoladas foram selecionadas 57 amostras, das quais se mensurou variáveis morfométricas em fotos digitalizadas no software AutoCAD e dendrométricas a partir de rolos de incremento coletados na altura do DAP. O desenvolvimento desta pesquisa teve como objetivo descrever as dimensões individuais e reconstituir o crescimento da copa e fuste de árvores isoladas de Cedrela fissilis, avaliado de 2007 a 2011, e construir equações matemáticas para descrever o crescimento da variável diâmetro da copa (DC), manto de copa (MC), diâmetro da copa em alturas relativas (DChi) e incremento periódico anual em área basal (IPAg). Nos alongamento anuais (ALG) foram verificados valores mínimo, máximo e médio anual de 3,0, 91,0 e 32,4 cm, respectivamente. Assim como correlações em série, determinada por r = 0,76 a 0,86 (Pr<.0001), tendo sido observados maiores alongamentos nas menores ordens de ramificação. Nos alongamentos periódicos (ALGP), correspondente ao período 2007-2011, verificaram-se valores médios de até 1,82 m, observado na classe diamétrica 30-40 cm, com coeficiente de variação (CV) máximo de 67,67%, verificado na classe > 60 cm. Para a construção dos modelos de crescimento foram selecionadas 35 árvores de acordo com sua condição de copa e fuste, sendo descartada a classe diamétrica > 60 cm devido a pouca amostragem. Para o manto de copa o modelo LNMC = b0+b1*(1/DAP)+b2*(DAP²) apresentou bom ajuste (R²aj.= 0,92 e CV = 6,12%). A equação da variável alongamento anual da copa, ALG=b0+b1*(LNICA)+b2*(DAP), apresentou o ajuste comprometido pelo alto erro percentual (R²aj. = 0,50; CV = 35,95%), descrevendo até 50% da variância total. Com precisão semelhante à ALG, o modelo ajustado para a variável crescimento da copa em diâmetro, CCD=b0+b1*(LNICA), apresentou altas taxas de erro percentual, com precisão estatística definida por CV = 36,25%; R²aj. = 0,44. Para o modelo DChi o ajuste foi descrito por R²aj.=0,58 e CV=52,41%, tendo sido definido o modelo LNDChi=b0+b1*(LNDAP)+b2*(1/hi²)+b3*(DAP²), tendo o mesmo não apresentado distribuição normal e heterogeneidade na variância dos resíduos. O ajuste da equação apara o IPAg apresentou boa precisão estatística (R²aj.=0,66; CV=11%), descrevendo até 66% da variância total a partir do modelo LNIPAg=b0+b1*(DAP)+b2*(h/d). Na avaliação descritiva dos incrementos observaram-se elevadas taxas de incremento periódico anual em diâmetro (IPAd) e IPAg nas classes diamétricas 25, 35 e 45 cm. Os valores de IPAd médio, mínimo e máximo foram de 3,6 cm, 0,7 e 7,3 cm, respectivamente. Nas classes 35 e 45 cm verificou-se taxa de IPAg média de 95,6 e 75,5 cm², respectivamente. Em todas as classes de diâmetro foram encontradas taxas de incremento corrente anual em diâmetro (ICAd) superior a 2,5 cm. As análises do crescimento da copa de árvore isoladas demonstraram que o crescimento rítmico da mesma e sua correlação com os incrementos do fuste possibilitam a construção de modelos de crescimento com boa eficiência estatística, porém, devendo se aperfeiçoar a estratificação fazendo uso de informações que descrevam as condições dos sítios. A metodologia de avaliação a partir de fotos digitalizadas também apresentou boa precisão e praticidade, podendo ser amplamente utilizada na avaliação de árvores singulares ou isoladas.
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33

Bennett, Jhono. "Platforms of engagement : a process of critical engagement with a developing context." Diss., University of Pretoria, 2011. http://hdl.handle.net/2263/29870.

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The South African population has been experiencing an unprecedented rate of urbanization that has left government bodies struggling to meet the qualitative and the infrastructural demands of the emergent sector in undeveloped areas. This dissertation aims to focus on the intensive networks found in these developing areas of vulnerability that display strong cohesion due to activities surrounding the production process. The premise presented is that in order to intervene architecturally with these networks, designers should critically engage these networks through participative processes of research, design and ideally construction. Through the author’s process of engagement, several key Architectural principles for an intervention emerge. Primarily the concept that a built intervention in a vulnerable settlement should first seek to associate itself with a network for its initial survival, and then aim to exist in a symbiotic relationship with this network through a mutually beneficial relationship. View Jhono Bennett's blog. Copyright 2011, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. Please cite as follows: Bennett, J 2011, Platforms of engagement : a process of critical engagement with a developing context, MArch(Prof) dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://upetd.up.ac.za/thesis/available/etd-11272011-161354 / > C12/4/36/gm
Dissertation (MArch(Prof))--University of Pretoria, 2011.
Architecture
unrestricted
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34

Houston, Brock Charles. "Comparison of Otolith-Based Growth Rates and Microchemistry in Red Drum Before, During, and After the Deepwater Horizon Oil Spill." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5963.

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Oil from the Deepwater Horizon blowout reached the Gulf of Mexico coast in the summer of 2010 and potentially exposed species living in those areas to toxic chemicals. The purpose of this study is to examine otoliths from Red Drum (Sciaenops ocellatus) for evidence of oil exposure that could be related to reduced growth rates. Because otolith growth and somatic growth are directly related, differences in annulus measurements can indicate differences in annual somatic growth, which is a good indicator of overall fish condition, and translates into changes in survival and lifetime reproductive potential. This study assessed variation in otolith elemental composition in years before, during, and after the oil spill using laser-ablation inductively-coupled plasma mass spectrometry, with emphasis on trace metals previously found in MC252 oil. Relative annual growth rates were estimated by calculating mean increment measurements for each age, and calculating a percentile for each observation. Growth was then compared with otolith elemental profiles. These two analyses were used to investigate associations between any observed growth variation and the temporal profiles of oil-indicator and stress-indicator elements. Otoliths obtained from Florida archaeological sites were used as a baseline for pre-industrial elemental compositions. Fish taken from 12 sampling sites in Florida and Louisiana with varying degrees of oil intrusion were analyzed for otolith element composition. Individual measurements were classified using Similarity Profile Analysis (SIMPROF, Clarke et al. 2008) and resulting SIMPROF groups were plotted on a seriated heat map to visualize elemental abundance groups. The largest group with the lowest elemental abundances was used as a reference group. This group was compared to higher-element abundance groups and to fossil otoliths found in Native American middens on Weedon Island, FL using nonparametric multivariate analysis of variance (NP-MANOVA) and Canonical Analysis of Principal Coordinates (CAP) to determine similarities of modern fish groups and an ancient baseline. Growth rates were then compared to the microchemistry groups to determine if there are any correlations with growth rates and otolith trace metal compositions. This study did not find any correlation between the Deepwater Horizon oil spill event and either Red Drum otolith microchemistry or growth. Otolith oil-metal concentrations did not vary significantly among study years, and there was no relationship between microchemistry and otolith-based growth rate. While there was decreased growth in 2010, the decreased growth appeared to be due to unusually cold winters during that year. Oil metal concentrations measured in the otoliths indicated continuous metal exposure rather than exposure to an episodic oil-spill event. This study also verified the use of archaeological otoliths as a viable microchemical baseline for pre-industrial otoliths. Preserved otolith material had very low hydrocarbon-associated metal concentrations, which is expected in otoliths that were formed before the period of heavy anthropogenic influence on coastal waters. This study represents a novel effort to compare pre-industrial-age microchemistry to the microchemistry of fish collected from impacted areas following a large oil spill.
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35

Bräker, Otto U., and Ernst Baumann. "Growth Reactions of Sub-Alpine Norway Spruce (Picea Abies (L.) Karst) Following One-Sided Light Exposure (Case Study at Davos "Lusiwald")." Tree-Ring Society, 2006. http://hdl.handle.net/10150/262646.

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In 1982, several rectangular openings were cut in a 100 year old sub-alpine Norway spruce forest stand to initiate regeneration at the Lusiwald site at Davos, Switzerland. The openings on the steep, north-facing slope created rapid changes to the environment of the border trees. Growth reactions of these border trees were compared and analysed with reference trees from the adjacent closed canopy stand in 1997. The radial growth pattern of the two data sets differed within the 14-year period since the openings were cut; the border trees showed growth releases. The growth reaction at the stem base was larger than at breast height. Changes in wind exposure may have influenced border trees to adapt their root systems. Sub-alpine Norway spruce stands aged around 100 years, which are usually considered slow-growing on a north aspect, still seem capable of reacting to greater resource availability such as sudden light changes.
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36

Felicia, Skorsdal. "Har det skett en förändring i abborrens (Perca fluviatilis) tillväxt i sjön Tåkern mellan år 1978 jämfört med år 2019?" Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166765.

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The growth in perch (Perca fluviatilis) is generally slow but varies depending on living conditions. For instance, growth is more rapid in warmer water temperature and when there is reduced intra- and interspecific competition for food. The cormorant (Phalacrocorax carbo) was established in Lake Tåkern in 1994 and could possibly have an effect on the growth of perch due to predation of small perch and competition for food with larger perch. The aim of this study was to examine whether the growth of perch had changed from year 1978, when a previous study on perch was preformed, to a recent fish survey in 2019 in lake Tåkern. The aim of the study was to assess if any changes in growth could be explained by predation and competition from cormorants. The aim of the study was also to examine whether there was a difference in growth between females and males. The age was determined by using the opercular bone and an age analysis was done to compare the growth between year 1978 and 2019. The results showed that the growth of 1-3-year-old perch was higher in year 1978 than in 2019. This was contrary to the expected outcome, that the predation from cormorants should had decreased competition for young perch in 2019. Previous studies on perch have shown a difference between males and females with an age over 2 years old. However, by the results there is no support that differences between males and females have affected the difference in growth at ages 1-3 years old between 1978 and 2019. As there was no difference between the sexes, any difference in growth between 1978 and 2019 could not be explained by an altered sex ratio. Since there were only a few older individuals 2019 comparison of growth for individuals over 4 years old were not possible to do. The conclusion is that there was no support that cormorants reduced the competition for smaller perch. Cormorants could possibly have contributed to low number of older individuals in 2019.
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37

Loiola, Táscilla Magalhães. "Manejo da paisagem em fragmentos de floresta de araucária no sul do Brasil com base no incremento diamétrico." Universidade do Estado de Santa Catarina, 2016. http://tede.udesc.br/handle/handle/2316.

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FAPESC
The objective of this study was used the geostatistics and dendrochronology together with morphometric variables and dendrometric for, based on the diameter increment, evaluate the growth in Araucaria angustifolia in southern Brazil, adjust growth models and generate mapping the distribution the increase for landscape management aimed at sustainable interventions in its ecosystem. Data were collected in native forest fragments in four areas distributed in three municipalities in the mountainous plateau of Santa Catarina: São Joaquim, Urupema and Panel. Were sampled 256 trees, which gathered up the dendrometric and morphometric variables, as well as its position in space. The morphometric analysis index indicated that the species is different degrees of competition. Covariance analysis showed no difference in the shape-size ratio in sample areas. The crown insertion height correlated positively and better fit with the overall height, and negatively correlated with the proportion of canopy. The negative correlation with pc% indicates that a higher percentage of canopy corresponding to minor hic. The relationship between the proportion of crown according to the canopy trees with length indicates that greater length cup mantle and have a higher proportion of canopy thus improved growth capacity. For the crown diameter according to the diameter at breast height it was a positive correlation, that is, with the increase in size increases with the diameter of the crown. Interdimensional relationships analyzed by covariance showed differences between growing trees in the forest and free growth. growing trees without competition have greater and greater pc% cc than trees growing in competition, as well as have higher DC than on growth in the forest. It was possible to determine the potential crown diameter, growth space, the number of trees per hectare and basal area per hectare, serving as a resource for future interventions of forest management. For the analysis of increment in diameter and the age, we used the trunk partial analysis. In São Joaquim 1 the average for the mean annual increment in diameter was 0, 45 cm.ano-1 in São Joaquim 2, was 0,69 cm.ano-1, Urupema, 0,82 cm.ano- 1 and Painel, 0,94 cm.ano-1. Covariance analysis showed no differences in the average annual increase in the study sites. The incremental adjustment in the diameter at breast height and age showed that the trees showed a gradual decrease in the increase with increase in diameter and advancing age. Pearson correlation analysis for the annual periodic increment in basal area with morphometric variables and dendrometric showed that the variables with the highest correlation were proportion of cup and diameter, with a positive correlation value of 0,40 and 0,30. The generalized linear model Gamma - identity presented the best statistical criteria in setting annual periodic increment in basal area by diameter, percentage of canopy and height. The use of cup dimensions variables can be inserted in the modeling of the annual periodic increment in basal area of Araucaria angustifolia. In geostatistical analysis initially evaluated the data from classical statistics, then proceeded to the adjustment of the semivariogram. Later, we used the ordinary kriging for the interpolation of data. The standard deviation values show that there is greater variability in the panel data. There is a positive skew for all data, making it necessary to be transformed in some cases. The exponential model demonstrated better adjustment to the areas of São Joaquin and Painel already in Urupema the best model resulted in the spherical model. With the data interpolation maps was possible to visualize the spatial distribution of mean annual increment in diameter covered the four sites, identifying the areas with the highest and lowest diameter increment. The results generated in this study can understand the structure and growth of distribution Araucaria in each study site, to facilitate the management of the landscape and the species in southern Brazil. Current legislation restricts the sustainable use of the species, its natural regeneration and the increase in the rates, so reforms are needed in the legislation to ensure the perpetuity of the type Araucaria Forest
O objetivo do presente trabalho foi utilizar a geoestatística e a dendrocronologia em conjunto com as variáveis morfométricas e dendrométricas para, com base no incremento diamétrico, avaliar o crescimento no tempo de Araucaria angustifolia no sul do Brasil, ajustar modelos de crescimento e gerar mapas da distribuição do incremento para manejo da paisagem visando intervenções sustentadas em seu ecossistema. Os dados foram coletados em fragmentos de floresta nativa, em quatro áreas distribuídas em três municípios do planalto serrano de Santa Catarina: São Joaquim, Urupema e Painel. Foram amostradas 256 árvores, das quais coletou-se as variáveis dendrométricas e morfométricas, como também seu posicionamento no espaço. A análise dos índices morfométricos indicou que a espécie encontra-se em diferentes graus de competição. A análise de covariância demonstrou que há diferença na relação forma-dimensão nas áreas de amostragem. A altura de inserção de copa apresentou correlação positiva e melhor ajuste com a altura total, e correlação negativa com a proporção de copa. A correlação negativa com pc% indica que um maior percentual de copa corresponde a menor hic. A relação entre a proporção de copa em função do comprimento de copa indica que árvores com maior comprimento de copa apresentam maior manto e proporção de copa, consequentemente, melhor capacidade de crescimento. Para o diâmetro de copa em função do diâmetro à altura do peito a correlação foi positiva, ou seja, com o aumento em dimensão aumenta proporcionalmente o diâmetro de copa. As relações interdimensionais, analisadas pela covariância, demonstraram diferenças entre árvores de crescimento na floresta e de crescimento livre. Árvores crescendo sem competição apresentam maior pc% e maior cc do que árvores crescendo em competição, assim como, apresentam maior dc do que sob crescimento no interior da floresta. Foi possível determinar o diâmetro de copa potencial, o espaço de crescimento, o número de árvores por hectare e área basal por hectare, servindo como subsídio para futuras intervenções de manejo florestal. Para a análise do incremento em diâmetro e da idade, utilizou-se da análise parcial de tronco. Em São Joaquim 1 a média para o incremento médio anual em diâmetro foi de 0,45 cm.ano-1, em São Joaquim 2, foi de 0,69 cm.ano-1, em Urupema, 0,82 cm.ano-1 e em Painel, 0,94 cm.ano-1. A análise de covariância mostrou existir diferenças no incremento médio anual nos sítios de estudo. O ajuste do incremento em função do diâmetro à altura do peito e da idade mostrou que as árvores apresentaram diminuição gradativa do incremento com aumento do diâmetro e avanço da idade. A análise de correlação de Pearson para o incremento periódico anual em área basal com as variáveis morfométricas e dendrométricas, demonstrou que as variáveis com maior correlação foram proporção de copa e diâmetro, com correlação positiva de valor 0,40 e 0,30. O modelo linear generalizado Gamma - identidade apresentou os melhores critérios estatísticos no ajuste do incremento periódico anual em área basal em função do diâmetro, percentual de copa e altura. O uso de variáveis de dimensões da copa, podem ser inseridas na modelagem do incremento periódico anual em área basal de Araucaria angustifolia. Na análise geoestatística inicialmente avaliou-se os dados a partir da estatística clássica, em seguida procedeu-se o ajuste dos semivariogramas. Posteriormente, utilizou-se da Krigagem ordinária para a interpolação dos dados. Os valores do desvio padrão mostram que há maior variabilidade nos dados de Painel. Existe uma assimetria positiva para todos os dados, tornando necessária a transformação dos mesmos em alguns casos. O modelo exponencial demostrou melhor ajuste para as áreas de São Joaquim e Painel, já em Urupema o melhor modelo resultou no modelo esférico. Com os mapas de interpolação dos dados foi possível visualizar a distribuição espacial do incremento médio anual em diâmetro nos quatro sítios abordados, identificando as áreas com maior e menor incremento em diâmetro. Os resultados gerados neste trabalho possibilitam perceber a estrutura e a distribuição de crescimento da araucária em cada sítio de estudo, contribuindo para o manejo da paisagem e da espécie no sul do Brasil. A legislação atual restringe o uso sustentável da espécie, sua regeneração natural e o aumento nas taxas de incremento, assim, são necessárias reformas na legislação vigente para garantir a perpetuidade da tipologia Floresta com Araucária
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38

Antoine, Daniel. "Evaluating the periodicity of incremental structures in dental enamel as a means of studying growth in children from past human populations." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.394732.

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39

Flores, Karen Stephanny Cordova. "Estudo das respostas ecofisiológicas no crescimento de clones Eucalyptus spp. submetidos a variações de níveis de restrições hídricas em distintas condições edáficas." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-28032016-121014/.

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A alta demanda por madeira de eucalipto para diversas finalidades traz a necessidade da expansão de plantios para áreas em condições de déficit hídrico, o que leva o interesse de entender os processos fisiológicos relacionados ao crescimento da árvore, para possibilitar uma alta produtividade das florestas nessas áreas. Com base nessas informações, o objetivo deste trabalho foi avaliar o efeito da variação de níveis de restrições hídricas em clones de Eucalyptus spp. plantados em diferentes condições edáficas, pelo estudo das respostas ecofisiológicas, para isso foram instalados em janeiro 2012 dois experimentos na Estação Experimental de Ciências Florestais de Itatinga (EECFI) pertencente a Escola Superior de Agricultura \"Luiz de Queiroz\" (ESALQ) - USP, o experimento 1 foi instalado no solo classificado como Latossolo vermelho distroférrico típico A moderado textura argilosa (LVdf) e o experimento 2 no solo Latossolo vermelho distrófico típico A moderado textura argilosa (LVd-1).Cada experimento foi implantado em blocos casualizados em arranjo fatorial de 6 x 3, seis clones de eucalipto (COP 1404, COP 1407, AEC 1528, AEC 0042, AEC 0224, AEC 0144) e três espaçamentos (3m x1m, 3mx2m, e 3mx4m), com seis repetições, e parcelas quadradas constituídas por 25 plantas, sendo as nove plantas centrais consideradas como a área útil de medição. Foram realizadas avaliações das variáveis: DAP (cm), altura total (m), comprimento da copa (m) e índice de área foliar (IAF m2/m2) trimestralmente, no período de 21 até 37 meses de idade para as variáveis altura total e DAP, e o comprimento da copa e IAF a partir do mês 27. Para a mensuração do IAF foram utilizados dois equipamentos LAI-2000, onde a coleta de dados foi fora e sob o dossel. O folhedo foi coletado mensalmente em todas as parcelas. A avaliação da eficiência e uso de água foi aos 29 e 35 meses, analisando área foliar e as caraterísticas estomáticas em quatro blocos, nos quais três árvores foram amostradas sistematicamente. Para avaliação no incremento de diâmetro no tronco, se instalaram faixas dendrométricas em duas árvores por parcela e as leituras foram quinzenais, sendo correlacionadas com variáveis climáticas no período de 15 e 45 dias de defasagem. Os clones que apresentaram melhor desenvolvimento e estratégia do uso da água foram AEC 1528, AEC 0144 e AEC 0042 obtendo como respostas: maior DAP, altura total, comprimento da copa, área foliar, diâmetro estomático, e menor IAF e concentração de estômatos. Em relação ao peso de folhedo depositado verificou-se que a tendência de deposição oscilou no decorrer do tempo em função da fenologia da planta. Na dinâmica de crescimento cambial os incrementos apresentaram correlações com as variáveis climáticas, principalmente com a precipitação pluviométrica, quanto maior a defasagem maior a correlação. Correlacionando todas as variáveis, os clones apresentaram distintos padrões de respostas ecofisiológicas.
Eucalypts plantations are expanding to drought áreas in Brazil in order to attend the high demand of eucalypts wood for various purposes. Therefore, the understanding the physiological process related to tree growth in this condition is one of the research priorities. This study aimed to evaluate the effect of ecophysiological responses to water restrictions levels in growth of Eucalyptus spp clones, planted in different soil conditions. The two field experiments were planted in January 2012 at the Itatinga Experimental Station, College of Agriculture \"Luiz de Queiroz\" (ESALQ), São Paulo State University. Experiment 1 was planted on a site which the soil is classified as \"A moderate typical dystrophic Red Latosol with clay texture (LVdf)\" and experiment 2 on \"A moderate typical dystrophic Red Latosol with clay texture (LVd- 1)\". The experiments were established in a randomized block design with factorial 6 x 3 arrangement [six eucalypts clones (COP 1404, COP 1407, AEC 1528 AEC 0042, AEC 0224, AEC 0144) and three spacings (3m x1m, 3mx2m and 3mx4m)], with six replications, and square plots (5x5 trees). The measurements were carried out on the nine central trees. From the 21 to 37 months of age, the following variables were assessed every three months: DBH (diameter at breast height in cm), height (m) and crown length (m). Leaf area index (LAI m2 / m2) was evaluated every three months after 27 months of age. Two LAI-2000 equipments were used to measure the LAI, one under and another out of the canopy. Litter was collected monthly on all plots. The efficiency of water use was evaluated at 29 and 35 months of age, based on leaf area and stomatal characteristics of samples collected in three trees sampled systematically in four blocks. Dendrometer belts were used to evaluate the diameter growth of two trees per plot. Data collected fortnightly from dendrometers belts were correlated with climatic variables with 15 and 45-da lags. AEC 1528, AEC 0144 and AEC 0042 clones showed higher DBH, total height, crown length, leaf area, stomatal diameter and lower IAF and stomatal concentration, showing better strategy of water use and growth. Deposition of litter fluctuated over time and varied with the tree phenology. Cambium growth dynamics correlated with climate variables, especially with the rainfall. Higher correlations were observed with higher measured lag. Clones showed distinct patterns of ecophysiological responses when the correlations of all variables were considered.
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40

Denneler, Bernhard, Yves Bergeron, and Yves Bégin. "Flooding Effects On Tree-Ring Formations Of Riparian Eastern White-Cedar (Thuja occidentalis L.), Northwestern Quebec, Canada." Tree-Ring Society, 2010. http://hdl.handle.net/10150/622612.

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Tree-ring formation of eastern white-cedar (Thuja occidentalis L.) at a boreal lake in northwestern Quebec, Canada, was monitored using manual band dendrometers to (i) retrace cambial activity phases, (ii) evaluate the effects of flooding on radial growth, and (iii) analyze the relationships with meteorological factors. The daily circumferential activity of four trees at each of two sites, a riparian and an upland site, was recorded during the growing season of 1996, a year with an extreme spring flood. First cambium cell divisions occurred near June 9, followed by a distinct and sustained upward trend in the stem basal area until mid-July that reflected the earlywood formation. The strongly synchronous circumferential activity at both sites suggests no adverse flooding effect on growth of the riparian trees, which is explained by the rapid retreat of the water just before growth initiation in early June. The following month until mid-August was characterized by strong short-term fluctuations caused by alternating drought and rain periods and a slight downward trend of the basal area for six of the eight banded white-cedars. The dendrometers of two trees, the closest to the lake, showed a slight upward trend probably reflecting latewood formation. Pearson correlation with meteorological data indicated that precipitation was positively related to the daily changes in basal area of all trees except during the period of earlywood formation, which probably resulted from the high soil moisture after spring snow-melting. Mean and minimum air humidity were positively related and maximum temperature negatively related to the daily variations in stem circumference during the whole monitoring period, emphasizing the importance of the internal water status on stem size.
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41

Cruz, Bobby. "Teachers' Knowledge, Perceptions, and Practices About Mindset in the Northern Mariana Islands." ScholarWorks, 2018. https://scholarworks.waldenu.edu/dissertations/5845.

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The problem studied was the poor academic achievement of middle school students in the Commonwealth of the Northern Mariana Islands (CNMI). Research indicates that a growth mindset positively affects a student's academic achievement and motivation to learn. However, despite the importance of mindset in fostering student success and enhancing learning, mindset remains underexplored in the CNMI. The purpose of this generic qualitative study was to fill this gap in knowledge by investigating teachers' knowledge, perceptions, and practices concerning mindset in the CNMI. Three research questions examined teachers' knowledge and perceptions of mindset in the CNMI and how teachers described and demonstrated the use of mindset in their practices. Dweck's seminal work on mindset served as the conceptual framework. Social constructivism guided the study process. Qualitative data were collected from 15 purposively sampled teachers at a local CNMI middle school. Data were analyzed through categorization and codification, from which emerging themes were used to answer research questions. Results indicated that teachers in the local middle school have limited knowledge and inaccurate perceptions regarding the mindset concept. Accordingly, the analysis recommended the need for and served as the basis for the design of a professional development workshop about mindset for teachers throughout the CNMI to enhance teacher instruction and improve student learning, thus promoting positive social change.
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42

Linkevicius, Edgaras. "Single Tree Level Simulator for Lituanian Pine Forests." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-150330.

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Ziele Die Forsteinrichtung in Litauen war in den vergangenen Jahrzehnten vom Leitgedanken geprägt, die Optimierung der Bestandsdichte und die Maximierung der Produktivität in jeder Phase der Bestandsentwicklung als gleichrangige Ziele zu betrachten. Deshalb wurden große Anstrengungen in die Herleitung von Bestandswuchsmodellen für gleichaltrige Kiefern- oder Fichtenreinbestände gelegt. Bei der Anwendung dieser Modelle auf gemischte oder in der Umwandlung befindliche Wälder sind allerdings nur ungenaue Resultate zu erzielen. Um den Erfordernissen einer zeitgemäßen Forstwirtschaft gerecht zu werden, sind geeignete Instrumente zur Prognose von Wachstum und Ertrag strukturreicher Wälder vonnöten. Das Hauptziel dieser Arbeit bestand deshalb in der Neuparametrisierung des Einzelbaumwachstumssimulators BWINPro-S (entwickelt für sächsische Wuchsverhältnisse) für Kiefernwälder auf mineralischen Standorten in Litauen. Zur Zielerreichung dienten folgende Schritte: • Schaffung und Evaluierung einer Datengrundlage für die Modellierung. • Abschätzung der Effekte von Konkurrenz um Wuchsraum auf den Durchmesser-, Grundflächen- und Höhenzuwachs von Einzelbäumen. • Entwicklung eines Durchmesser-Zuwachsmodells sowie Neuparametrisierung der Grundflächen- und Höhenwachstumsmodelle. • Bestimmung der Einzelbaummortalität durch Konkurrenz um Wuchsraum. • Entwicklung eines ersten Ansatzes für einen Einzelbaumwachstumssimulator für Kiefer in Litauen. Hypothesen: 1. Die Standorteigenschaften sind der prägende Faktor für Wachstum und Ertrag von Waldbeständen. 2. Distanzabhängige Konkurrenzindizes zeigen höhere partielle Korrelationen zu Grundflächen- und Höhenzuwachs der Einzelbäume als distanzunabhängige Konkurrenzindizes. 3. Im Vergleich zum Ursprungsmodell BWINPro-S kann durch die Neuparametrisierung eine bessere Anpassung an die Wachstumswirklichkeit in Litauen erzielt werden (in Bezug auf Durchmesser-, Grundflächen- und Höhenzuwachs sowie Mortalitätsschätzung). 4. Ein Einzelbaumwachstumssimulator unterstützt die Entscheidungsträger und Forstplaner in Litauen bei der Optimierung der Waldbewirtschaftung ganz wesentlich. Material und Methoden Der Forschungsansatz gliederte sich wie folgt: 1) Vervollständigung der Datengrundlage. 2) Analyse der Konkurrenzverhältnisse. 3) Modellierung des Einzelbaumwachstums. 4) Validierung der neuentwickelten bzw. neuparametrisierten Modelle. Die Datengrundlage bestand aus Messwerten von 18 Dauerversuchsflächen (PEP) und zwei Validierungsflächen (VP), von denen letztere nur zur Modellüberprüfung herangezogen wurden. Auf allen Flächen stocken vorwiegend aus Naturverjüngung hervorgegangene, einschichtige Kiefernbestände auf kieferntypischen Standorteinheiten. Die Vervollständigung der Datengrundlage erforderte (a) die Erzeugung der Ausgangsdatenbasis, (b) Berechnung fehlender Werte, und (c) Evaluierung der vervollständigten Datengrundlage. Dabei lag das Hauptaugenmerk auf: • Stichprobenumfang und Schätzung der Populationsmittelwerte. • Schätzung des potentiellen Standort-Leistungsvermögens. • Analyse der Beziehung zwischen dem potentiellen Standort-Leistungsvermögen und dem tatsächlichen Waldertrag. Zur Abschätzung der Effekte von Konkurrenz um Wuchsraum auf den Durchmesser-, Grundflächen- und Höhenzuwachs von Einzelbäumen diente folgendes Vorgehen: Zur Konkurrentenidentifikation wurde ein inverser Lichtkegel mit einem Öffnungswinkel von 60 und 80 Grad konstruiert, dessen nach unten gerichtete Spitze (a) an der Kronenansatzhöhe, (b) an der Höhe der größten Kronenbreite, und (c) am Stammfuß des Zentralbaumes ansetzte. Zur Quantifizierung des Konkurrenzdrucks wurden mit Hilfe der partiellen Korrelationsanalyse 20 Konkurrenzindizes geprüft, von denen letztendlich sechs distanzabhängige und zwei distanzunabhängige Indizes in der weiteren Auswertung Berücksichtigung fanden. Die Modellierung des Einzelbaumwachstums erfolgte in drei Schritten: (a) Entwicklung eines originären Einzelbaum-Durchmesserzuwachsmodells, (b) Neuparametrisierung des Grundflächen- und Höhenzuwachsmodells, und (c) Entwicklung und Neuparametrisierung von Mortalitätsmodellen. Zur Bewertung einfacher linearer Regressionsmodelle wurden die statistische Signifikanz und das Bestimmtheitsmaß herangezogen. Bei multiplen linearen Regressionsmodellen wurde die Signifikanz jeder unabhängigen Variablen gesondert geprüft (hinsichtlich Normalverteilung, Varianzhomogenität der Residuen und Multikollinearität). Zur Bewertung einfacher nichtlinearer Regressionsmodelle diente in erster Linie das korrigierte Bestimmtheitsmaß, bei multiplen nichtlinearen Regressionsmodellen fanden darüber hinaus Q-Q-Plots (Quantil-Quantil-Diagramme) und die Prüfung auf Varianzhomogenität der Residuen Verwendung. Die Evaluierung multipler logistischer Regressionsmodelle erfolgte mit Pearsons Chi-Quadrat-Test, die Signifikanz jedes Modellparameters wurde mit der Wald-Statistik geprüft. Die Anpassungsgüte wurde mit Hilfe der Log-Likelihood-Funktion, Cox & Snell- bzw. Nagelkerke-Bestimmtheitsmaßen, Klassifikationstabellen und ROC-Kurven bewertet. Zur Prüfung der neuparametrisierten Grundflächen- und Höhenzuwachsmodelle wurden die modellierten Werte gegen die Messwerte und darüber hinaus die Residuen gegen die Modellwerte geplottet. Außerdem wurden zur Beurteilung die Verzerrung, die Präzision und die Treffgenauigkeit (sowohl als Absolut- als auch als Relativwerte) herangezogen. Ergebnisse und Schlussfolgerungen Die Wachstumsmodelle des Simulators BWINPro-S konnten erfolgreich an die Bedingungen in Litauen angepasst werden. Daraus lassen sich folgende Schlussfolgerungen ableiten: 1. Der stehende Vorrat und die Gesamtwuchsleistung von Kiefernbeständen werden nur z. T. vom standörtlichen Leistungsvermögen determiniert. Die Standorteigenschaften bestimmen das theoretische Leistungsvermögen von Beständen. Ob dieses Potential auch tatsächlich ausgeschöpft werden kann, hängt weitgehend von der Bewirtschaftungsart ab, die geprägt ist durch Beginn, Häufigkeit und Stärke der Durchforstungseingriffe. 2. In Kiefernreinbeständen eignen sich distanzabhängige Konkurrenzindizes besser zur Prognose des mittleren Grundflächenzuwachses als distanzunabhängige Indizes. Zur Beschreibung des Einzelbaum-Durchmesserzuwachses hat sich der Index nach BIGING & DOBBERTIN (1992, in dieser Arbeit als Index CI4 bezeichnet) in Kombination mit der Konkurrentenidentifikationsmethode „Suchkegelansatz in Kronenansatzhöhe, Öffnungswinkel 80 Grad“ als der bestgeeignetste Ansatz erweisen. 3. Der distanzunabhängige Konkurrenzindex nach HEGYI (1974) erreichte die höchsten partiellen Korrelationskoeffizienten mit den mittleren Einzelbaum-Höhenzuwächsen und ergab etwas bessere Resultate bei der Wachstumsprognose als distanzabhängige Indizes. Allerdings waren die Beziehungen zwischen den Konkurrenzindizes und den Einzelbaum-Höhenzuwächsen nur schwach ausgeprägt. 4. Konkurrenz wirkt sich dämpfend auf den Einzelbaum-Durchmesserzuwachs aus, bei zunehmender Konkurrenz sinkt der Zuwachs kontinuierlich ab. Im Gegensatz dazu beschleunigt leichte Konkurrenz das Einzelbaum-Höhenwachstum, bei starker Konkurrenz jedoch wird auch der Höhenzuwachs negativ beeinflusst. 5. Das im Rahmen dieser Arbeit hergeleitete nichtlineare Durchmesserzuwachsmodell ist zur Prognose des Kiefernwachstums bestens geeignet, das Bestimmtheitsmaß beträgt 0,483, die Residuen waren normalverteilt. 6. Die Neuparametrisierung des Grundflächen- und Höhenzuwachsmodells verbesserte die Anpassung an die Wuchsbedingungen in Litauen bedeutend. Eine erste Validierung, durchgeführt für eine Wachstumsprognose über einen 30-jährigen Zeitraum, ergab zufriedenstellende Ergebnisse. 7. Die zwei im Rahmen dieser Arbeit hergeleiteten Mortalitätsschätzer sind zur Vorhersage der natürlichen Absterbeprozesse in den Kiefernbeständen gut geeignet. Beide Ansätze klassifizierten lebende und tote Bäume mit einer Treffgenauigkeit von über 83%, während der in BWINPro-S enthaltene Schätzer nur 77% der Bäume korrekt zuordnete. 8. Der für litauische Verhältnisse neuparametrisierte Wachstumssimulator BWINPro-S ist ein wichtiges Instrument zur Entscheidungsunterstützung für Forstplaner in Litauen
Objectives In Lithuania, during the most recent decades, the leading theory in forest management and planning combined optimization of forest stand density and maximal productivity at every time point of stand development. Thus, great effort was spent in creating stand level models that are highly effective in managing even-aged monocultures of pine or spruce forests. But these models produce significant errors in mixed or converted forests. In order to meet the requirements of contemporary forestry, appropriate forest management tools are required that would be capable to predict the growth and yield of more structured forests. Thus, the overall objective for this study was to re-parameterise the single tree level simulator BWINPro-S (developed for forests in Saxony/Germany) for Lithuanian pine forests that grow on mineral sites. To reach this goal, the following tasks were set: • To create, and to evaluate, a database for modelling. • To estimate the impact of competition for growing space on diameter, basal area and height growth of trees. • To develop a tree diameter model, and re-parameterise basal area and height growth models. • To assess natural tree mortality induced by competition between trees for growing space. • To develop the first approach of STLS for pine in Lithuania. Hypotheses 1. Site quality is the most important factor that affects forest growth and yield. 2. Distance dependent Competition Indices had higher partial correlation with tree basal area and height increment than distance independent Competition Indices. 3. The re-parameterised model based on Lithuanian data fits better under Lithuanian conditions (regarding diameter, basal area, height increment and mortality) than the original model BWINPro-S. 4. A single tree level simulator provides valuable support for decision makers and forest managers to improve forest management in Lithuania. Materials and methods To reach the main goals of this study, the research was structured to four sections: 1) Database completion, 2) Analysis of competition, 3) Modelling tree growth, 4) Validation of developed models. The database consisted of analytical data from 18 permanent experimental plots (PEPs) and 2 Validation Plots (VP) that were used only for the validation of the models. All plots (PEPs and VP) represent mainly naturally regenerated, single layer pine stands that grow on very typical pine sites. Database completion involved (a) establishment of the initial database, (b) modelling of missing data values and (c) evaluation of the complete database, which focused on: • Sample size and estimation of the population’s mean • Estimation of potential site productivity • Estimation of relationship between potential site productivity and forest yield In order to estimate the impact of competition for growing space on diameter, basal area and height growth of trees the following methods were used. To select the competitors, this study focuses on three separate positions for setting the inverse cone: a) at the height of the crown base, b) at the height of widest crown width, and c) at the stem base. The opening angle of the search cone was either 60 or 80 degrees. To estimate the competition, the study by partial correlation analysis evaluated a total of 20 competition indices, of which six distance dependent and two distance independent CIs were applied in the research programme. Modelling of tree growth was divided into three parts: a) development of an original tree diameter increment model, b) re-parameterisation of basal area and height increment models, and c) development of new natural mortality models and re-parameterisation of natural mortality models. Simple linear regression models were evaluated by estimating each model’s statistical significance and coefficient of determination. Statistical analysis of multiple linear regression models was enlarged by conducting further tests: statistical significance was checked for each independent variable: regression assumptions (concerning normal distribution and homogeneity of variance of the models’s residuals, and multicollinearity of the independent variables) were checked. Simple nonlinear regression models were evaluated mainly by adjusted coefficient of determination. For multiple nonlinear regression models, regression assumptions were also checked by producing normal Q-Q plots and by checking homogeneity of variance of model’s residuals. Multiple logistic regression models were evaluated by estimating each model’s statistical significance with Pearson’s chi square statistics and the statistical significance of each model’s parameters with Wald statistics. Goodness of fit was estimated by using log likelihood function values, Cox-Snell and Nagelkerkle’s coefficients of determination, classification tables and ROC curves. The re-parameterised basal area and height increment models were validated by plotting each model’s predicted values against observed values. Also each model’s residuals were plotted against predicted values. Bias, relative bias, precision, relative precision, accuracy and relative accuracy when comparing predicted and observed values were estimated as well. Results and Conclusions The growth models used in the BWINPro-S simulator were successfully re-parameterised for Lithuanian growth conditions. Thus the study may state these conclusions: 1. The accumulated standing volumes and overall productivity of pine stands only partially depends on the productivity potential of sites. Site quality defines the growth potential that could be reached in a stand. The realization of growth potential largely depends on the growing regime in the stand that is defined by the beginning, frequency and intensity of thinning. 2. In pure pine stands, distance dependent competition indices show greater capabilities to predict mean annual basal area increment than distance independent indices. Competition index (coded as CI4 in this study) proposed by BIGING & DOBBERTIN (1992) combined with the selection method height to crown base with opening angle of 80 degrees is recommended as the most efficient for describing the individual diameter growth of trees. 3. HEGYI\\\'S (1974) distance independent competition index scored the highest partial correlation coefficients and produced slightly better results than distance dependent competition indices in predicting mean annual height increment for individual trees. Yet, the generally poor performance of competition indices to predict height increment of individual pine trees was also recorded. 4. Competition has a purely negative impact on tree diameter growth. Increasing competition leads to steady decreases in diameter increment. Nevertheless, although a small amount of competition does stimulate tree height growth, stronger competition has a lasting negative impact on tree height growth. 5. The nonlinear diameter increment model, developed by this study, has high capabilities to predict growth of pine trees. The model’s coefficient of determination value was equal to 0.483. The distribution of the model’s residuals fulfilled the requirements of regression assumptions. 6. The re-parameterisation of the BWINPro-S basal area and height increment models for use in Lithuanian permanent experimental plots, increased their performance. During the first validation procedure, based on 30 years growth simulation, the re-parameterised models produced reliable results. 7. Two individual mortality models, developed by this study, showed very high capabilities to predict the natural mortality of pine trees. The distance dependent natural mortality model scored slightly better results. Both models managed to correctly classify dead and living trees, slightly more than 83% of the time. The re-parameterisation of the BWINPro-S natural mortality model increased its ability to predict the natural mortality of pine trees in Lithuania. Correctly classifying growing and dead trees increased by 6%, from 77 to 83%. 8. BWINPro-S simulator with re-parameterised growth models for Lithuanian conditions is a valuable support tool for decision makers and forest managers in Lithuania
Darbo tikslai Lietuvoje ilgą laiką ūkininkavimas miškuose buvo grindžiamas medynų tankumo optimizavimu ir maksimalaus medynų produktyvumo siekimu visose medynų vystymosi stadijose. Mokslininkai dėjo daug pastangų kurdami medyno lygmens našumo modelius. Šie modeliai buvo patikimi ūkininkaujant vienaamžiuose medynuose. Tačiau jie yra sunkiai pritaikomi mišriuose medynuose. Siekiant patenkinti šiuolaikinio miškininkavimo poreikius, kai vis didesnis dėmesys skiriamas mišrių medynų su keliais ardais auginimui, reikalingi nauji modeliai, kurie sėkmingai prognozuotų mišrių medynų augimą, jų našumą bei reakcijas į įvairias ūkines priemones. Todėl pagrindinis šio darbo tikslas yra parametrizuoti iš naujo BWINPro-S medžio lygio stimuliatorių sukurtą Vokietijos rytinėje žemėje Saksonijoje taip pritaikant jį Lietuvos sąlygoms. Šiam tikslui pasiekti, buvo suformuluoti sekantys uždaviniai: • Paruošti ir įvertinti duomenų bazę reikalingą modeliavimui. • Įvertinti medžių tarpusavio konkurencijos įtaką medžių skersmens, skerspločių sumos ir aukščio prieaugiui. • Sukurti naują medžio skersmens prieaugio modelį ir parametrizuoti iš naujo skerspločių sumos bei aukščio modelius. • Įvertinti pušynų savaiminio retinimosi dėsningumus atsižvelgiant į medžių tarpusavio konkurenciją dėl augimo erdvės. Tikrintinos hipotezės: 1. Medyno augavietė yra svarbiausias veiksnys, lemiantis medynų našumą ir produktyvumą. 2. Konkurencijos indeksai, įvertinantys atstumą tarp medžių, turi didesnes dalinės koreliacijos reikšmes su medžių skerspločių sumos, skersmens ir aukščio prieaugiais lyginant su konkurencijos indeksais, neįvertinančiais atstumo tarp medžių. 3. Parametrizuoti naujai, panaudojant Lietuvoje augančių pušynų duomenis, modeliai geriau tinka Lietuvos sąlygoms (pagal skersmens, skerspločių sumos ir aukščio prieaugį bei savaiminį retinimąsi) lyginant su modeliais, sukurtais Vokietijos sąlygoms. 4. Medžio lygmens augimo simuliatorius yra naudinga priemonė miškų valdytojams siekiant pagerinti ūkininkavimo kokybę Lietuvoje. Darbo metodai Šis darbas buvo suskirstytas į keturias pagrindines dalis: 1) duomenų bazės suformavimas, 2) konkurencijos indeksų analizė, 3) medžių augimo modeliavimas, 4) augimo modelių patikrinimas. Duomenų bazę sudarė 20 pastovių tyrimo barelių, iš kurių 18 buvo skirti modelių kūrimui ir 2 modelių patikrinimui. Tyrimo bareliai buvo įsteigti natūraliai atsikūrusiuose vienaardžiuose pušynuose, augančiuose tipingose pušiai augavietėse. Duomenų bazės įvertinimas buvo atliekamas tokiais etapais: (a) pirminės duomenų bazės suformavimas, (b) trūkstamų matavimų modeliavimas ir (c) duomenų bazės įvertinimas yra grindžiamas: • Imties dydžiu ir populiacijos vidurkio nustatymo tikslumu. • Potencialaus medynų našumo įvertinimu. • Ryšių tarp potencialaus medynų našumo ir medynų našumo bei produktyvumo įvertinimu. Vertinant konkurencijos įtaką medžių skersmens, skerspločių sumos ir aukščio prieaugiui, buvo naudoti konkurentų parinkimo ir konkurencijos įvertinimo metodai. Konkuruojantys medžiai buvo atrenkami pagal apversto kūgio viršūnę, sutapatintą su tiriamojo medžio a) lajos pradžia, b) plačiausia lajos vieta, ir c) medžio šaknies kakleliu. Kūgio kampas buvo keičiamas nuo 60 iki 80 laipsnių. Iš viso buvo tiriama dvidešimt konkurencijos indeksų (du konkurencijos indeksai, nepriklausantys nuo atstumo tarp medžių ir aštuoniolika konkurencijos indeksų, priklausančių nuo atstumo tarp medžių). Konkurencijos indeksai vertinti taikant dalinės koreliacijos metodus. Medžių augimo modeliavimas buvo atliekamas trim etapais: a) originalaus medžių skersmens prieaugio modelio sukūrimas, b) medžių skerspločių sumos ir medžių aukščio prieaugio modelių parametrizavimas naujai, c) sukūrimas originalių ir parametrizavimas naujai jau esamų natūralaus retinimosi modelių. Paprastieji tiesinės regresijos modeliai buvo vertinami naudojant jų statistinį reikšmingumą ir skaičiuojant determinacijos koeficientą. Daugialypių tiesinės regresijos modelių statistinė analizė buvo išplėsta papildomais testais: statistinis reikšmingumas tiriamas kiekvienam nepriklausomam kintamajam, taip pat vertinama ar modelis tenkina pagrindines regresijos sąlygas (nepriklausomi kintamieji nėra tarpusavyje susieti, modelio liekanos turi normalųjį skirstinį, yra tolygiai išsidėstę). Paprastieji netiesinės regresijos modeliai buvo vertinami skaičiuojant koreguotąjį determinacijos koeficientą. Atliekant daugialypių netiesinės regresijos modelių analizę taip pat buvo tikrinama ar tenkinamos regresijos sąlygos. Logistiniai savaiminio retinimosi modeliai buvo vertinami naudojant šiuos statistinius parametrus: modelio X2 suderinamumo kriterijų, Voldo kriterijų, didžiausio tikėtinumo funkcijos vertę, Kokso-Snelo ir Nagelkerkės pseudodeterminacijos koeficientus, klasifikavimo lenteles ir klasifikatoriaus jautrumo ir specifiškumo (ROC) kreives. Parametrizuoti naujai medžių skerspločių sumos ir medžių aukščio prieaugių modeliai buvo tikrinami lyginant modeliuotas medžių skersmens ir aukščio reikšmes su realiai išmatuotomis reikšmėmis analizuojamo periodo pabaigoje. Taip pat buvo tiriamas modelių liekanų išsidėstymas modeliuojamų verčių atžvilgiu. Galiausiai, poslinkio, santykinio poslinkio, tikslumo, santykinio tikslumo, tikslumo be poslinkio ir santykinio tikslumo be poslinkio buvo naudojami vertinant modelių prognozes. Rezultatai ir išvados Augimo modeliai, naudojami BWINPro-S medžio lygio simuliatoriuje, buvo sėkmingai parametrizuoti naujai ir pritaikyti Lietuvos sąlygoms. Remiantis šio darbo rezultatais, buvo gautos sekančios išvados: 1. Sukauptas tūris ir bendras medynų našumas pušynuose tik dalinai priklauso nuo potencialaus augaviečių derlingumo. Augavietės sąlygos lemia tik potencialų medynų našumą kuris gali būti pasiektas medyne. Ar potencialus augavietės našumas bus realizuotas priklauso nuo medžių auginimo rėžimo, kuris apibūdinamas ugdomųjų kirtimų pradžia, kartojimų dažnumu ir jų intensyvumu. 2. Grynuose pušynuose, konkurencijos indeksai, įvertinantys atstumą tarp medžių turi didesnes galimybes prognozuoti skerspločių sumos prieaugį negu konkurencijos indeksai, neįvertinantys atstumo tarp medžių. Konkurencijos indeksas CI4, pasiūlytas BIGING & DOBBERTIN (1992), grindžiamas konkurentų parinkimu pagal apverstą 80 laipsnių kūgį, kurio viršūnė yra sutapatinama su medžių lajos pradžia yra rekomenduojamas kaip pats efektyviausias modeliuojant medžių skersmens prieaugį. 3. HEGYI (1974) konkurencijos indeksas, neįvertinantis atstumo tarp medžių tiriant konkurencijos indeksų įtaką medžių aukščio prieaugiui, parodė kiek geresnius dalinės koreliacijos rezultatus negu kad konkurencijos indeksai, įvertinantys atstumą tarp medžių. Tyrimų rezultatai parodė gana silpną konkurencijos indeksų galimybę prognozuoti medžių aukščio prieaugį. 4. Konkurencija turi išskirtinai neigiamą įtaką medžių skersmens prieaugiui. Didėjanti konkurencija lemia mažėjantį skersmens prieaugį. Nedidelė konkurencija padidina medžių aukščio prieaugį. Tačiau stipresnė konkurencija taip pat turi neigiamą įtaką medžių aukščio prieaugiui. 5. Originalus skersmens prieaugio modelis turi geras galimybes prognozuoti pušies medžių augimą. Šio modelio determinacijos koeficientas buvo lygus 0.483. Modelio liekanos turėjo normalųjį skirstinį ir buvo tolygiai pasiskirsčiusios modeliuojamų verčių atžvilgiu. 6. Parametrizuoti naujai BWINPro-S medžių skerspločių sumos ir medžių aukščio prieaugio modeliai, panaudojant Lietuvos pušynų pastovių tyrimo barelių duomenis, padidino jų prognozavimo galimybes. Pirmieji modelių tikrinimo rezultatai pagrįsti trisdešimties metų augimo prognozėmis, parodė, kad šie modeliai yra patikimi. 7. Du originaliai sukurti pušynų savaiminio retinimosi modeliai pasižymi geromis galimybėmis prognozuoti pušynų savaiminį išsiretinimą. Savaiminio retinimosi modelis, atsižvelgiantis į atstumą tarp medžių pasižymi geresnėmis galimybėmis prognozuoti pušynų savaiminį retinimąsi negu savaiminio retinimosi modelis, neatsižvelgiantis į atstumą tarp medžių. Abu modeliai teisingai klasifikavo daugiau negu 83% augančių ir savaime išsiretinančių medžių. BWINPro-S savaiminio retinimosi modelio parametrizavimas naujai padidino jo teisingai prognozuojamų augančių ir savaime išsiretinančių medžių dalį šešiais procentais, nuo 77 iki 83%. 8. Medžio lygio augimo simuliatorius BWINPro-S su parametrizuotais naujai augimo modeliais yra naudingas įrankis Lietuvos miškų augintojams
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43

Zanon, Magda Lea Bolzan. "Crescimento da Araucaria angustifolia (Bertol.) Kuntze diferenciado por dioicia." Universidade Federal de Santa Maria, 2007. http://repositorio.ufsm.br/handle/1/3799.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
This study was conducted at São Francisco de Paula National Forest, Rio Grande do Sul, Brazil, in Araucaria angustifolia (Bertol.) Kuntze implanted stands, aiming to study the growth periodicity from male and female trees having 40 and 60 years and to correlate this growth with meteorological, morphometric and environmental variables. The growth behavior was obtained through a biweekly inspection based on the diametric tapes positioned at diameter at breast height in 96 trees, evaluated from August 2003 to August 2006. The results allowed to conclude that the beginning of the annual growth happens in September, having its peak in January, starting to decrease since March, being influenced by the competition conditions, vitality and canopy area, not having statistical difference of trees growth between male and female trees, even so it is verified a tendency that female trees develop more than male trees. The meteorological variables, like temperature and precipitation, are directly correlated with the increment. The temperature and precipitation increase influences positively in increment. The precipitation occurrence followed by low temperatures reduces the growth. There was no inclination level difference for increment curves in male and female trees for basal area, allowing to use a unique model to describe the trees growth.
O presente trabalho foi desenvolvido em povoamentos de Araucaria angustifolia (Bertol.) Kuntze implantados na Floresta Nacional de São Francisco de Paula, Município de São Francisco de Paula, RS, com o objetivo de estudar a periodicidade de crescimento de árvores masculinas e femininas, dominantes e dominadas, com idades de 40 e 60 anos, e correlacionar esse crescimento com as variações meteorológicas, morfométricas e ambientais. O comportamento do crescimento foi obtido partindo do acompanhamento quinzenal de periodicidade por meio da instalação de fitas dendrométricas no diâmetro a altura do peito de 96 árvores, avaliadas durante o período de agosto de 2003 a agosto de 2006. Os resultados deste trabalho permitiram concluir que o início do crescimento anual das árvores ocorre em setembro, tendo seu pico de crescimento no mês de janeiro, começando a decrescer a partir de março, sendo influenciado pelas condições de competição, vitalidade e área de copa das árvores, não havendo diferença estatística de crescimento entre árvores femininas e masculinas, embora se verifique uma tendência das árvores femininas se desenvolverem mais do que as masculinas. As variáveis meteorológicas, como temperatura e precipitação, estão diretamente correlacionada com o incremento. O aumento da temperatura e da precipitação influi positivamente no incremento. A ocorrência de precipitação acompanhada de temperaturas baixas reduz o crescimento. Não houve diferença de inclinação e nível para as curvas de incremento em área basal de árvores do sexo masculino e feminino, permitindo ser utilizado um modelo único para descrever o crescimento das árvores.
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44

Mostauskis, Henrikas. "Metinių rievių deformacijos tyrimai medžiams senstant." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2005. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2005~D_20050606_132204-39140.

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Research report on deformation of annual rings is given in the thesis. Aim of the work - to perform an analysis of deformation of annual rings during obsolescence of tree. Tasks of the work - to perform a comparative analysis using borings made in 2004 and 1985 – 1986. To evaluate statistical reliability of deformation of annual rings. Object of the work - trees of Scotch pine (Pinus sylvestris L.). Methods of the work – methods of verification of statistical hypotheses and analysis of variance were used for data processing. Content of the work – verification of hypothesis that annual rings of pine is shrinking during the obsolescence of trees. Results: - difference of annual rings width is statistically reliable at two point of the interval investigated: nearby bark and in the central part of the stem, at the margin where sapwood is converting to heartwood. The shrinking reaches 0.2 mm within 5 annual rings. The biggest influence on shrinking of annual rings has distance of annual rings from the bark and age of tree.
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45

Bennison, Linda Louise. "Accountability in a horticultural marketing co-operative: Perceptions from grower members." Thesis, Queensland University of Technology, 2019. https://eprints.qut.edu.au/136515/2/Linda_Bennison_Thesis.pdf.

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Horticultural co-operatives play an important role in food quality and security, economic stability and the welfare of regional and rural communities around the world. In this qualitative study, a conceptual framework of accountability using: to whom; for what; how; with what standards; and with what consequences has been adopted. Semi-structured interviews with growers revealed co-operative principles were not uniformly prioritised and new dimensions of accountability, latent and incremental, were evident. These findings, relevant to global food security, aid understanding of accountability in the fresh food supply chain and contribute to thinking about co-operatives.
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46

Bergqvist, Göran. "Stand and wood properties of boreal Norway spruce growing under birch shelter /." Umeå : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5642-8.pdf.

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47

Дробоног, А. М. "Моделювання вимушеного циклотронного випромінювання". Master's thesis, Сумський державний університет, 2020. https://essuir.sumdu.edu.ua/handle/123456789/81389.

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В роботі проведено математичне та комп’ютерне моделювання взаємодії електронного потоку, що рухається вздовж осі системи та циркулярно поляризованої електромагнітної хвилі за умови вимушеного циклотронного випромінювання. Знайдені аналітичні співвідношення, що визначають оптимальні параметри системи: електронний пучок – електромагнітна хвиля. На базі методу великих частинок створена комп’ютерна модель, що описує динаміку обміну енергії між електронним пучком та електромагнітною хвилею. Показано якісну узгодженість між аналітичними розрахунками та комп’ютерним моделюванням вимушеного циклотронного випромінювання.
В роботі проведено математичне та комп’ютерне моделювання взаємодії електронного потоку, що рухається вздовж осі системи та циркулярно поляризованої електромагнітної хвилі за умови вимушеного циклотронного випромінювання. Знайдені аналітичні співвідношення, що визначають оптимальні параметри системи: електронний пучок – електромагнітна хвиля. На базі методу великих частинок створена комп’ютерна модель, що описує динаміку обміну енергії між електронним пучком та електромагнітною хвилею. Показано якісну узгодженість між аналітичними розрахунками та комп’ютерним моделюванням вимушеного циклотронного випромінювання.
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48

Mettanurak, Thammarat. "Effect of Minimum Suppression and Maximum Release Years on Compression Parallel to Grain Strength and Specific Gravity for Small-sized Yellow-poplar (Liriodendron tulipifera L.) Specimens." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/34804.

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Several researchers have concluded that there is little or no relationship between specific gravity and ring width or growth rate in yellow-poplar (Liriodendron tulipifera L.). Because most mechanical properties of wood are also closely related to specific gravity, it would thus be of interest to learn how minimum suppression and maximum release yearsâ evidence that can be extracted from radial growth patterns based on a modified radial growth averaging (RGA) techniqueâ influence the compression parallel to grain strength and specific gravity of wood.

This study is designed to evaluate the effects of growth suppression and release on ultimate crushing stress and specific gravity for small-sized yellow-poplar specimens. Additionally, the relationship between specific gravity and ultimate crushing stress is investigated.

Twenty-three yellow-poplar cores were examined for their growth ring widths. Minimum suppression and maximum release years were identified based on the modified RGA criteria method. From each increment core, three 1 Ã 1 Ã 4 mm specimens from both minimum suppression and maximum release years were tested for their ultimate crushing stresses using a micro-mechanical test system. The specific gravity of each specimen was also recorded. These data were analyzed using a paired samples t test and a simple linear regression.

The results indicate that the mean ultimate crushing stress and specific gravity of maximum release years were significantly higher than that of minimum suppression years. Furthermore, the ultimate crushing stress was linearly related to the specific gravity of the specimens.
Master of Science

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49

Aliouane-Shaw, Hocine. "Application des théories de la complexité à la planification et à la gestion de l’espace des campus universitaires : l’exemple du campus bordelais (Talence-Pessac-Gradignan)." Thesis, Bordeaux 3, 2019. http://www.theses.fr/2019BOR30051.

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Анотація:
La révolution numérique bouleverse la pratique universitaire et impacte de manière significative l’organisation spatiale des institutions d’enseignement supérieur. Pourtant, le système de planification spatial de ces territoires d’innovation et de communication intense continue de se référer à des schémas directeurs qui ne permettent pas d’intégrer en temps réel, les changements en matière de pratique universitaire et de faire évoluer les structures physiques en conséquence. Se situant dans une perspective d’aménagement et de planification urbaine, la recherche interroge les outils qui régissent actuellement l’aménagement de l’espace universitaire dans le monde, en accordant une attention particulière aux tentatives d’actualiser les modes de gestion de l’espace qui s’appuient sur les avancées dans le domaine des sciences de la communication et de l’information et leur application à la gestion des systèmes complexes. La recherche se donne ainsi pour objet d’explorer en quoi une application des théories de la complexité à l’univers des campus permettrait d’adapter leur système de planification et de gestion à l’imprévisibilité des bouleversements en cours, tout en autorisant l’adaptation continue des structures physiques à ces évolutions. Après avoir explicité la genèse et la teneur des principales théories de la complexité dans le champ scientifique, la recherche explore leur application à la planification urbaine, à travers notamment le modèle de planification mis en place sur le campus d’Eugene en Oregon en 1974 par l’architecte Christopher Alexander. La compréhension de ce modèle singulier permet de mettre en perspective les outils et les méthodes de planification en vigueur sur les sites universitaires en France, et notamment sur le campus bordelais TPG. La recherche analyse ainsi les méthodes et outils d’aménagement déployés par les deux institutions universitaires afin d’intégrer (en temps réel ou décalé), les changements intervenant dans la pratique universitaire (modes d’apprentissage et de transmission des connaissances, recherche), tout en faisant évoluer les structures physiques du campus
The digital revolution is disrupting university practice and significantly impacting the spatial organization of higher education institutions. However, the spatial planning system of these territories of innovation and intense communication still continues to refer to master plans that do not allow changes in university practice to be integrated in real time and does not enable physical structures to evolve accordingly. Stemming from an urban planning and development perspective, this research questions the tools that currently govern the development of university space around the world, paying particular attention to attempts to update spatial management methods based on advances in the field of communication and information sciences and their application to the management of complex systems. The research thus aims to explore how an application of complexity theories to campus development would adapt the university’s planning and management system to the unpredictability of ongoing shifts, while allowing for the continuous adaptation of physical structures to these changes. After explaining the genesis and content of the main complexity theories in the scientific field, the research explores their application to urban planning, in particular through the planning model set up on the Eugene campus in Oregon in 1974 by architect Christopher Alexander. Understanding this unique model allows us to put into perspective the planning tools and methods in use at university sites in France, and in particular on the Bordeaux TPG campus. The research thus analyses the planning methods and tools used by the two university institutions in order to integrate (in real or delayed time) changes in university practice (learning and knowledge transmission methods, research), while adapting the physical structures of the campus
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Li, Ping, and 李屏. "A study on early growth of jack mackerel (Trachurus japonicus) in the northeastern waters off Taiwan by otolith daily growth increments." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/07304613663229612803.

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碩士
國立臺灣海洋大學
環境生物與漁業科學學系
103
Jack mackerel Trachurus japonicus, widely distributed in the East China Sea and coastal waters of Japan, Korea, and Taiwan, is one of the most important fish resources in the northeastern waters off Taiwan. In recent years, many studies regarding the age, growth and reproduction of jack mackerel has been reported. However, the information of their early life history in the northeastern waters off Taiwan is still unknown. In order to solve the problem, the larval samples collected from different sources in the study area during 2005-2014 were used to determine age information of larval fish. The relationship between body length and daily age of the samples preserved by ethanol solution was established, with which the daily age of the samples preserved by formalin solution. A total of 402 larvae samples were analyzed, with body length from 1.5 to 7.3 mm and the ages were estimated from 0 to 30 days. Gompertz growth equation was used to describe the biological characteristics of age and growth of early life. The results are summarized as follow: (1) The distribution of jack mackerel in the northeastern waters off Taiwan was dominated by small larvae of body length ranged from 3-4 mm, which indicates that northeastern waters off Taiwan were spawning grounds and the nursery grounds for jack mackerel. (2) Initial length of the jack mackerel is 1.47 mm, growth rate of early life stage is 2.30 mm/d, and the decreasing growth rate is 0.04 mm/d. (3) Growing rates of larvae increases significantly from preflexion stage to flexion stage and slows down thereafter. (4) The hatching date distribution estimated by daily rings indicated that jack mackerel tends to spawn at the periods of new moon and half-moon.
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